workaround a problem with 'grep -e' tests under Solaris

m4/m4.spec

@@ -33,7 +33,7 @@ Class:        CORE
 Group:        MacroProcessor
 License:      GPL
 Version:      1.4.7
-Release:      20060925
+Release:      20060926
 
 #   list of sources
 Source0:      ftp://ftp.gnu.org/gnu/m4/m4-%{version}.tar.gz
@@ -67,6 +67,7 @@ AutoReqProv:  no
     #   configure package
     CC="%{l_cc}" \
     CFLAGS="%{l_cflags -O}" \
+    GREP="grep" \
     ./configure \
         --prefix=%{l_prefix} \
         --datarootdir=%{l_prefix} \