diff -ruN ucspi-tcp-0.88-factory/rblsmtpd.c ucspi-tcp-0.88-rss2/rblsmtpd.c
--- ucspi-tcp-0.88-factory/rblsmtpd.c	2000-03-18 10:18:42.000000000 -0500
+++ ucspi-tcp-0.88-rss2/rblsmtpd.c	2008-12-08 22:54:40.000000000 -0500
@@ -60,16 +60,54 @@
 
 void rbl(char *base)
 {
+  int i;
+  char *altreply = 0;
   if (decision) return;
   if (!stralloc_copy(&tmp,&ip_reverse)) nomem();
+  i = str_chr(base, ':');
+  if (base[i]) {
+    base[i] = 0;
+    altreply = base+i+1;
+  }
   if (!stralloc_cats(&tmp,base)) nomem();
-  if (dns_txt(&text,&tmp) == -1) {
-    flagmustnotbounce = 1;
-    if (flagfailclosed) {
-      if (!stralloc_copys(&text,"temporary RBL lookup error")) nomem();
-      decision = 2;
+  if (altreply) {
+    if (dns_ip4(&text,&tmp) == -1) {
+      flagmustnotbounce = 1;
+      if (flagfailclosed) {
+        if (!stralloc_copys(&text,"temporary RBL lookup error")) nomem();
+        decision = 2;
+      }
+      return;
+    }
+    if (text.len) {
+      if(!stralloc_copys(&text, "")) nomem();
+      while(*altreply) {
+        char *x;
+        i = str_chr(altreply, '%');
+        if(!stralloc_catb(&text, altreply, i)) nomem();
+        if(altreply[i] &&
+           altreply[i+1]=='I' &&
+           altreply[i+2]=='P' &&
+           altreply[i+3]=='%') {
+          if(!stralloc_catb(&text, ip_env, str_len(ip_env))) nomem();
+          altreply+=i+4;
+        } else if(altreply[i]) {
+          if(!stralloc_cats(&text, "%")) nomem();
+          altreply+=i+1;
+        } else {
+          altreply+=i;
+        }
+      }
+    }
+  } else {
+    if (dns_txt(&text,&tmp) == -1) {
+      flagmustnotbounce = 1;
+      if (flagfailclosed) {
+        if (!stralloc_copys(&text,"temporary RBL lookup error")) nomem();
+        decision = 2;
+      }
+      return;
     }
-    return;
   }
   if (text.len)
     if (flagrblbounce)
@@ -157,7 +195,7 @@
 {
   int flagwantdefaultrbl = 1;
   char *x;
-  int opt;
+  int opt, i;
 
   ip_init();
 
@@ -174,6 +212,24 @@
       decision = 2;
     }
   }
+  if (text.len) {
+    if(!stralloc_copy(&tmp,&text)) nomem();
+    if(!stralloc_0(&tmp)) nomem();
+    if(!stralloc_copys(&text, "")) nomem();
+    for(x=tmp.s;*x;) {
+      i = str_chr(x, '%');
+      if(!stralloc_catb(&text, x, i)) nomem();
+      if(x[i] && x[i+1]=='I' && x[i+2]=='P' && x[i+3]=='%') {
+        if(!stralloc_catb(&text, ip_env, str_len(ip_env))) nomem();
+        x+=i+4;
+      } else if(x[i]) {
+        if(!stralloc_cats(&text, "%")) nomem();
+        x+=i+1;
+      } else {
+        x+=i;
+      }
+    }
+  }
 
   while ((opt = getopt(argc,argv,"bBcCt:r:a:")) != opteof)
     switch(opt) {