Use Perl 5 even if Perl 4 comes first in the search path.

Configure

@@ -731,7 +731,8 @@ sub which
 		{
 		if (-x "$path/$name")
 			{
-			return "$path/$name";
+			return "$path/$name" unless ($name eq "perl" and
+			 system("$path/$name -e " . '\'exit($]<5.0);\''));
 			}
 		}
 	}

config

@@ -344,13 +344,15 @@ fi
 if [ ".$PERL" = . ] ; then
 	for i in . `echo $PATH | sed 's/:/ /g'`; do
 		if [ -f "$i/perl" ] ; then
-			PERL="$i/perl"
-			break;
+			if "$i/perl" -e 'exit($]<5.0)'; then
+				PERL="$i/perl"
+				break;
+			fi;
 		fi;
 	done
 fi
 
-if $PERL -e 'exit($]>=5.0);' ; then
+if [ ".$PERL" = . ] ; then
 	echo "You need Perl 5."
 	exit 1
 fi