diff -ur postgresql-7.4.5/src/bin/psql/startup.c postgresql-7.4.5_hack/src/bin/psql/startup.c
--- postgresql-7.4.5/src/bin/psql/startup.c	2003-09-29 20:21:33.000000000 +0200
+++ postgresql-7.4.5_hack/src/bin/psql/startup.c	2004-10-07 01:34:32.656452439 +0200
@@ -280,9 +280,12 @@
 		}
 
 		/* Default values for variables that are used in interactive case */
-		SetVariable(pset.vars, "PROMPT1", DEFAULT_PROMPT1);
-		SetVariable(pset.vars, "PROMPT2", DEFAULT_PROMPT2);
-		SetVariable(pset.vars, "PROMPT3", DEFAULT_PROMPT3);
+		if (!GetVariable(pset.vars, "PROMPT1"))
+			SetVariable(pset.vars, "PROMPT1", DEFAULT_PROMPT1);
+		if (!GetVariable(pset.vars, "PROMPT2"))
+			SetVariable(pset.vars, "PROMPT2", DEFAULT_PROMPT2);
+		if (!GetVariable(pset.vars, "PROMPT3"))
+			SetVariable(pset.vars, "PROMPT3", DEFAULT_PROMPT3);
 
 		if (!options.no_psqlrc)
 			process_psqlrc();