aautogen.sh, change a `sed' expression to be more defensive

ChangeLog

@@ -1,3 +1,11 @@
+2010-09-21  Robert Larice
+ * autogen.sh :
+    there are several implementations of `sed'.
+    Some can't swallow a '\n' escape sequence on the RHS.
+    And some want a plain newline in the RHS to be escaped.
+    see http://sed.sourceforge.net/sedfaq4.html#s4.1
+     `4.1. How do I insert a newline into the RHS of a substitution?'
+
 2010-09-19 Dietmar Warning
  * adms/hicum2/admsva/hicum2.va: update to version 2.24 with small exceptions
    from the original source code, seems the last update because model provider

autogen.sh

@@ -147,8 +147,12 @@ if [ "$ADMS" -eq 1 ]; then
     znew=`awk '$1 ~ /#VLAMKF/ { print " " $2 "\\\\" }' < configure.ac`
 
     # Find "tests/vbic/Makefile" and insert the list of Makefiles
+    # some sed's fail to process the '\n' escape on the RHS,
+    #   thus use an escaped plain newline
     sed \
-        -e "s,tests\\/vbic\\/Makefile,&\\n  $znew ," \
+        -e "s,tests\\/vbic\\/Makefile,&\\
+$znew
+ ," \
         configure.ac > temp-adms.ac
 
     for adms_dir in `ls $ADMSDIR` ; do