Index: src/backend/utils/misc/guc.c
===================================================================
RCS file: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v
retrieving revision 1.339
diff -c -c -r1.339 guc.c
*** src/backend/utils/misc/guc.c	13 Aug 2006 02:22:24 -0000	1.339
--- src/backend/utils/misc/guc.c	13 Aug 2006 15:34:13 -0000
***************
*** 5512,5518 ****
  		{
  			struct config_string *conf = (struct config_string *) record;
  
! 			return strcmp(*conf->variable, newvalue) == 0;
  		}
  	}
  
--- 5512,5521 ----
  		{
  			struct config_string *conf = (struct config_string *) record;
  
! 			if (!*conf->variable)	/* custom variable with no value yet */
! 				return false;
! 			else
! 				return strcmp(*conf->variable, newvalue) == 0;
  		}
  	}