--- make.1	17 Dec 2002 19:01:18 -0000	1.29.2.15
+++ make.1	16 Mar 2004 11:12:09 -0000
@@ -1266,6 +1266,17 @@ 
 \&.endfor
 .Ed
 won't work, and should be rewritten the other way around.
+.Pp
+Undefined variables are not expanded when assigned with expansion.
+This is intentional, but may lead to surprising results:
+.Bd -literal
+VAR1:=  Assigned with${OUT} expansion
+VAR2!=  echo Assigned with${OUT} expansion
+OUT=    out
+all:
+    @echo := - ${VAR1}
+    @echo != - ${VAR2}
+.Ed
 .Sh SEE ALSO
 .Xr mkdep 1 ,
 .Xr make.conf 5