diff -uw old/hdrline.c new/hdrline.c
--- old/hdrline.c	2010-10-04 12:12:37.000000000 +0100
+++ new/hdrline.c	2010-10-04 12:13:19.000000000 +0100
@@ -414,6 +414,97 @@
 	const char *cp;
 	struct tm *tm, *TM; 
 	time_t t, T;
+	int i = 0, invert = 0;
+
+	if (optional && (op == '[' || op == '(')) {
+	  char *is, res = 's';
+	  T = time(NULL);
+	  tm = localtime(&T);
+
+	  is = (char *)prefix;
+	  if( *is == '>' ) {
+	    invert = 1;
+	    ++is;
+	  }
+
+	  while( *is && *is != '?' ) {
+	    int t = strtol (is, &is, 10);
+	    switch (*(is++)) {
+	      case '?':
+		break;
+	      case 'y':
+		t *= 365 * 24 * 60 * 60;
+		res = 'y';
+		break;
+	      case 'M':
+		t *= 30 * 24 * 60 * 60;
+ 		res = 'M';
+		break;
+	      case 'w':
+		t *= 7 * 24 * 60 * 60;
+		res = 'w';
+		break;
+	      case 'd':
+		t *= 24 * 60 * 60;
+		res = 'd';
+		break;
+	      case 'h':
+		t *= 60 * 60;
+		res = 'h';
+		break;
+	      case 'm':
+		t *= 60;
+		res = 'm';
+		break;
+	    }
+	    i += t;
+	  }
+
+	  /* if (i < 0) */
+	  /*   i *= -1; */
+
+	  switch (res) {
+	    case 'y':
+	    case 'M':
+	    case 'w':
+	    case 'd':
+	      switch (res) {
+	        case 'y':
+		  T = T - (tm->tm_yday - 1) * 24 * 60 * 60;
+		  i = i - 365 * 24 * 60 * 60;
+		  break;
+	        case 'M':
+		  T = T - (tm->tm_mday - 1) * 24 * 60 * 60;
+		  i = i - 30 * 24 * 60 * 60;
+		  break;
+	        case 'w':
+		  T = T - (tm->tm_wday - 1) * 24 * 60 * 60;
+		  i = i - 7 * 24 * 60 * 60;
+		  break;
+	        case 'd':
+		  i = i - 24 * 60 * 60;
+		  break;
+	      }
+	      T = T - tm->tm_hour * 60 * 60 + tm->tm_min * 60 + tm->tm_sec;
+	      break;
+
+	    case 'h':
+	      T = T - tm->tm_min * 60 + tm->tm_sec;
+	      i = i - 60 * 60;
+	      break;
+
+	    case 'm':
+	      T = T - tm->tm_sec;
+	      i = i - 60;
+	      break;
+	  }
+
+	  /* T -= (op == '(') ? hdr->received : hdr->date_sent; */
+	  if( T - ((op == '(') ? hdr->received : hdr->date_sent) > i )
+	    optional = 0;
+	  break;
+	}
+
 
 	p = dest;
 
diff -uw old/muttlib.c new/muttlib.c
--- old/muttlib.c	2010-10-04 12:11:02.000000000 +0100
+++ new/muttlib.c	2010-10-04 12:12:53.000000000 +0100
@@ -1228,7 +1228,16 @@
       if (*src == '?')
       {
 	flags |= M_FORMAT_OPTIONAL;
-	src++;
+	ch = *(++src); /* save the character to switch on */
+	cp = prefix;
+	++src;
+	count = 0;
+	while (count < sizeof (prefix) && *src != '?')
+	{
+	  *cp++ = *src++;
+	  count++;
+	}
+	*cp = 0;
       }
       else
       {
@@ -1244,12 +1253,12 @@
 	  count++;
 	}
 	*cp = 0;
-      }
 
       if (!*src)
 	break; /* bad format */
 
       ch = *src++; /* save the character to switch on */
+      }
 
       if (flags & M_FORMAT_OPTIONAL)
       {
diff -uw old/PATCHES new/PATCHES
--- old/PATCHES	2010-10-04 12:12:00.000000000 +0100
+++ new/PATCHES	2010-10-04 12:12:53.000000000 +0100
@@ -1,4 +1,5 @@
 sidebar
+patch-1.5.0.ats.date_conditional.1
 dgc.deepif.1
 dgc.subjrx
 fg.smarttime