--- cyrus-imapd-2.2.6/imap/message.c.acceptinvalidfrom	2004-10-30 15:03:02.220642392 -0700

+++ cyrus-imapd-2.2.6/imap/message.c	2004-10-30 15:06:01.838336352 -0700

@@ -229,6 +229,8 @@

     int reject8bit = config_getswitch(IMAPOPT_REJECT8BIT);

     int munge8bit = config_getswitch(IMAPOPT_MUNGE8BIT);

     int inheader = 1, blankline = 1;

+    char is_from;

+    static const char * from_header = "From ";

     while (size) {

 	n = prot_read(from, buf, size > 4096 ? 4096 : size);

@@ -294,8 +296,20 @@

 	/* Check for valid header name */

 	if (sawnl && buf[0] != ' ' && buf[0] != '\t') {

 	    if (buf[0] == ':') return IMAP_MESSAGE_BADHEADER;

-	    for (p = (unsigned char *)buf; *p != ':'; p++) {

-		if (*p <= ' ') return IMAP_MESSAGE_BADHEADER;

+            p = (unsigned char *) buf;

+            if (*p == '>')

+                p++;

+            if (*p == from_header[0])

+                is_from = 0;

+            else

+                is_from = -1;

+            for (; *p != ':' && is_from < 5; p++) {

+                if (is_from > 0 && *p != from_header[is_from])

+                    is_from = -1;

+                if (is_from >= 0)

+                    is_from++;

+                else

+                    if (*p <= ' ') return IMAP_MESSAGE_BADHEADER;

 	    }

 	}