new file mode 100644
--- /dev/null
+++ b/src/mail/ngx_mail.c
@@ -0,0 +1,416 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_event.h>
+#include <ngx_mail.h>
+
+
+static char *ngx_mail_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
+static int ngx_libc_cdecl ngx_mail_cmp_conf_in_addrs(const void *one,
+    const void *two);
+
+
+ngx_uint_t  ngx_mail_max_module;
+
+
+static ngx_command_t  ngx_mail_commands[] = {
+
+    { ngx_string("mail"),
+      NGX_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_NOARGS,
+      ngx_mail_block,
+      0,
+      0,
+      NULL },
+
+    { ngx_string("imap"),
+      NGX_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_NOARGS,
+      ngx_mail_block,
+      0,
+      0,
+      NULL },
+
+      ngx_null_command
+};
+
+
+static ngx_core_module_t  ngx_mail_module_ctx = {
+    ngx_string("mail"),
+    NULL,
+    NULL
+};
+
+
+ngx_module_t  ngx_mail_module = {
+    NGX_MODULE_V1,
+    &ngx_mail_module_ctx,                  /* module context */
+    ngx_mail_commands,                     /* module directives */
+    NGX_CORE_MODULE,                       /* module type */
+    NULL,                                  /* init master */
+    NULL,                                  /* init module */
+    NULL,                                  /* init process */
+    NULL,                                  /* init thread */
+    NULL,                                  /* exit thread */
+    NULL,                                  /* exit process */
+    NULL,                                  /* exit master */
+    NGX_MODULE_V1_PADDING
+};
+
+
+static char *
+ngx_mail_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
+{
+    char                        *rv;
+    u_char                      *text;
+    size_t                       len;
+    ngx_uint_t                   i, a, l, m, mi, s, p, last, bind_all, done;
+    ngx_conf_t                   pcf;
+    ngx_array_t                  in_ports;
+    ngx_listening_t             *ls;
+    ngx_mail_listen_t           *imls;
+    ngx_mail_module_t           *module;
+    ngx_mail_in_port_t          *imip;
+    ngx_mail_conf_ctx_t         *ctx;
+    ngx_mail_conf_in_port_t     *in_port;
+    ngx_mail_conf_in_addr_t     *in_addr;
+    ngx_mail_core_srv_conf_t   **cscfp;
+    ngx_mail_core_main_conf_t   *cmcf;
+
+    if (cmd->name.data[0] == 'i') {
+        ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
+                           "the \"imap\" directive is deprecated, "
+                           "use the \"mail\" directive instead");
+    }
+
+    /* the main mail context */
+
+    ctx = ngx_pcalloc(cf->pool, sizeof(ngx_mail_conf_ctx_t));
+    if (ctx == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    *(ngx_mail_conf_ctx_t **) conf = ctx;
+
+    /* count the number of the http modules and set up their indices */
+
+    ngx_mail_max_module = 0;
+    for (m = 0; ngx_modules[m]; m++) {
+        if (ngx_modules[m]->type != NGX_MAIL_MODULE) {
+            continue;
+        }
+
+        ngx_modules[m]->ctx_index = ngx_mail_max_module++;
+    }
+
+
+    /* the mail main_conf context, it is the same in the all mail contexts */
+
+    ctx->main_conf = ngx_pcalloc(cf->pool,
+                                 sizeof(void *) * ngx_mail_max_module);
+    if (ctx->main_conf == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+
+    /*
+     * the mail null srv_conf context, it is used to merge
+     * the server{}s' srv_conf's
+     */
+
+    ctx->srv_conf = ngx_pcalloc(cf->pool, sizeof(void *) * ngx_mail_max_module);
+    if (ctx->srv_conf == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+
+    /*
+     * create the main_conf's, the null srv_conf's, and the null loc_conf's
+     * of the all mail modules
+     */
+
+    for (m = 0; ngx_modules[m]; m++) {
+        if (ngx_modules[m]->type != NGX_MAIL_MODULE) {
+            continue;
+        }
+
+        module = ngx_modules[m]->ctx;
+        mi = ngx_modules[m]->ctx_index;
+
+        if (module->create_main_conf) {
+            ctx->main_conf[mi] = module->create_main_conf(cf);
+            if (ctx->main_conf[mi] == NULL) {
+                return NGX_CONF_ERROR;
+            }
+        }
+
+        if (module->create_srv_conf) {
+            ctx->srv_conf[mi] = module->create_srv_conf(cf);
+            if (ctx->srv_conf[mi] == NULL) {
+                return NGX_CONF_ERROR;
+            }
+        }
+    }
+
+
+    /* parse inside the mail{} block */
+
+    pcf = *cf;
+    cf->ctx = ctx;
+
+    cf->module_type = NGX_MAIL_MODULE;
+    cf->cmd_type = NGX_MAIL_MAIN_CONF;
+    rv = ngx_conf_parse(cf, NULL);
+
+    if (rv != NGX_CONF_OK) {
+        *cf = pcf;
+        return rv;
+    }
+
+
+    /* init mail{} main_conf's, merge the server{}s' srv_conf's */
+
+    cmcf = ctx->main_conf[ngx_mail_core_module.ctx_index];
+    cscfp = cmcf->servers.elts;
+
+    for (m = 0; ngx_modules[m]; m++) {
+        if (ngx_modules[m]->type != NGX_MAIL_MODULE) {
+            continue;
+        }
+
+        module = ngx_modules[m]->ctx;
+        mi = ngx_modules[m]->ctx_index;
+
+        /* init mail{} main_conf's */
+
+        if (module->init_main_conf) {
+            rv = module->init_main_conf(cf, ctx->main_conf[mi]);
+            if (rv != NGX_CONF_OK) {
+                *cf = pcf;
+                return rv;
+            }
+        }
+
+        for (s = 0; s < cmcf->servers.nelts; s++) {
+
+            /* merge the server{}s' srv_conf's */
+
+            if (module->merge_srv_conf) {
+                rv = module->merge_srv_conf(cf,
+                                            ctx->srv_conf[mi],
+                                            cscfp[s]->ctx->srv_conf[mi]);
+                if (rv != NGX_CONF_OK) {
+                    *cf = pcf;
+                    return rv;
+                }
+            }
+        }
+    }
+
+    /* mail{}'s cf->ctx was needed while the configuration merging */
+
+    *cf = pcf;
+
+
+    if (ngx_array_init(&in_ports, cf->temp_pool, 4,
+                       sizeof(ngx_mail_conf_in_port_t))
+        != NGX_OK)
+    {
+        return NGX_CONF_ERROR;
+    }
+
+    imls = cmcf->listen.elts;
+
+    for (l = 0; l < cmcf->listen.nelts; l++) {
+
+        /* AF_INET only */
+
+        in_port = in_ports.elts;
+        for (p = 0; p < in_ports.nelts; p++) {
+            if (in_port[p].port == imls[l].port) {
+                in_port = &in_port[p];
+                goto found;
+            }
+        }
+
+        in_port = ngx_array_push(&in_ports);
+        if (in_port == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        in_port->port = imls[l].port;
+
+        if (ngx_array_init(&in_port->addrs, cf->temp_pool, 2,
+                           sizeof(ngx_mail_conf_in_addr_t))
+            != NGX_OK)
+        {
+            return NGX_CONF_ERROR;
+        }
+
+    found:
+
+        in_addr = ngx_array_push(&in_port->addrs);
+        if (in_addr == NULL) {
+            return NGX_CONF_ERROR;
+        }
+
+        in_addr->addr = imls[l].addr;
+        in_addr->ctx = imls[l].ctx;
+        in_addr->bind = imls[l].bind;
+    }
+
+    /* optimize the lists of ports and addresses */
+
+    /* AF_INET only */
+
+    in_port = in_ports.elts;
+    for (p = 0; p < in_ports.nelts; p++) {
+
+        ngx_qsort(in_port[p].addrs.elts, (size_t) in_port[p].addrs.nelts,
+                  sizeof(ngx_mail_conf_in_addr_t), ngx_mail_cmp_conf_in_addrs);
+
+        in_addr = in_port[p].addrs.elts;
+        last = in_port[p].addrs.nelts;
+
+        /*
+         * if there is the binding to the "*:port" then we need to bind()
+         * to the "*:port" only and ignore the other bindings
+         */
+
+        if (in_addr[last - 1].addr == INADDR_ANY) {
+            in_addr[last - 1].bind = 1;
+            bind_all = 0;
+
+        } else {
+            bind_all = 1;
+        }
+
+        for (a = 0; a < last; /* void */ ) {
+
+            if (!bind_all && !in_addr[a].bind) {
+                a++;
+                continue;
+            }
+
+            ls = ngx_listening_inet_stream_socket(cf, in_addr[a].addr,
+                                                  in_port[p].port);
+            if (ls == NULL) {
+                return NGX_CONF_ERROR;
+            }
+
+            ls->backlog = -1;
+            ls->rcvbuf = -1;
+            ls->sndbuf = -1;
+
+            ls->addr_ntop = 1;
+            ls->handler = ngx_mail_init_connection;
+            ls->pool_size = 256;
+
+            /* STUB */
+            ls->log = *cf->cycle->new_log;
+            ls->log.data = &ls->addr_text;
+            ls->log.handler = ngx_accept_log_error;
+            /**/
+
+            imip = ngx_palloc(cf->pool, sizeof(ngx_mail_in_port_t));
+            if (imip == NULL) {
+                return NGX_CONF_ERROR;
+            }
+
+            ls->servers = imip;
+
+            in_addr = in_port[p].addrs.elts;
+
+            if (in_addr[a].bind && in_addr[a].addr != INADDR_ANY) {
+                imip->naddrs = 1;
+                done = 0;
+
+            } else if (in_port[p].addrs.nelts > 1
+                       && in_addr[last - 1].addr == INADDR_ANY)
+            {
+                imip->naddrs = last;
+                done = 1;
+
+            } else {
+                imip->naddrs = 1;
+                done = 0;
+            }
+
+#if 0
+            ngx_log_error(NGX_LOG_ALERT, cf->log, 0,
+                          "%ui: %V %d %ui %ui",
+                          a, &ls->addr_text, in_addr[a].bind,
+                          imip->naddrs, last);
+#endif
+
+            imip->addrs = ngx_pcalloc(cf->pool,
+                                    imip->naddrs * sizeof(ngx_mail_in_addr_t));
+            if (imip->addrs == NULL) {
+                return NGX_CONF_ERROR;
+            }
+
+            for (i = 0; i < imip->naddrs; i++) {
+                imip->addrs[i].addr = in_addr[i].addr;
+                imip->addrs[i].ctx = in_addr[i].ctx;
+
+                text = ngx_palloc(cf->pool,
+                                  INET_ADDRSTRLEN - 1 + sizeof(":65535") - 1);
+                if (text == NULL) {
+                    return NGX_CONF_ERROR;
+                }
+
+                len = ngx_inet_ntop(AF_INET, &in_addr[i].addr, text,
+                                    INET_ADDRSTRLEN);
+
+                len = ngx_sprintf(text + len, ":%d", in_port[p].port) - text;
+
+                imip->addrs[i].addr_text.len = len;
+                imip->addrs[i].addr_text.data = text;
+            }
+
+            if (done) {
+                break;
+            }
+
+            in_addr++;
+            in_port[p].addrs.elts = in_addr;
+            last--;
+
+            a = 0;
+        }
+    }
+
+    return NGX_CONF_OK;
+}
+
+
+static int ngx_libc_cdecl
+ngx_mail_cmp_conf_in_addrs(const void *one, const void *two)
+{
+    ngx_mail_conf_in_addr_t  *first, *second;
+
+    first = (ngx_mail_conf_in_addr_t *) one;
+    second = (ngx_mail_conf_in_addr_t *) two;
+
+    if (first->addr == INADDR_ANY) {
+        /* the INADDR_ANY must be the last resort, shift it to the end */
+        return 1;
+    }
+
+    if (first->bind && !second->bind) {
+        /* shift explicit bind()ed addresses to the start */
+        return -1;
+    }
+
+    if (!first->bind && second->bind) {
+        /* shift explicit bind()ed addresses to the start */
+        return 1;
+    }
+
+    /* do not sort by default */
+
+    return 0;
+}