use libplumb instead
diff --git a/src/cmd/sam/mkfile b/src/cmd/sam/mkfile
index 8402579..e677d39 100644
--- a/src/cmd/sam/mkfile
+++ b/src/cmd/sam/mkfile
@@ -13,7 +13,6 @@
 	mesg.$O\
 	moveto.$O\
 	multi.$O\
-	plumb.$O\
 	rasp.$O\
 	regexp.$O\
 	shell.$O\
@@ -27,4 +26,6 @@
 	errors.h\
 	mesg.h\
 
+SHORTLIB=plumb 9
+
 <$PLAN9/src/mkone