diff --git a/cards.scm b/cards.scm
index 462b1dd..3b0bb95 100644
--- a/cards.scm
+++ b/cards.scm
@@ -35,6 +35,7 @@
 	 (chicken base)
 	 (chicken sort)
 	 (chicken format)
+	 (chicken irregex)
 	 dictionary
 	 members-base
 	 member-record)
@@ -69,7 +70,9 @@
 		      (cardname (sprintf "~A~A~A"
 					 nick
 					 (if aliased? "." "")
-					 (if aliased? calias ""))))
+					 (if aliased?
+					     (irregex-replace/all (irregex " " 'u) calias "_")
+					     ""))))
 		 (print cardname " " cardid)
 		 (cloop (cdr cards)))))
 	   (uloop (cdr srecs)))))))