Fixed typo: Using --with-dbm had no effect because due to a typo it
was never enabled.
diff --git a/configure.in b/configure.in
index 55e93cd..8e9d83c 100644
--- a/configure.in
+++ b/configure.in
@@ -923,7 +923,7 @@
[ --with(out)-dbm disable/enable dbm module])
# enabled by default but one of the dbm.h files must be found
-if test "$ac_cv_header_dbm_h" = "yes" -o "$ac_cv_header_db1_ndbm_h" = "yes" -o "$ac_cv_header_gdbm_ndbm_h" = "yes"
+if test "$ac_cv_header_ndbm_h" = "yes" -o "$ac_cv_header_db1_ndbm_h" = "yes" -o "$ac_cv_header_gdbm_ndbm_h" = "yes"
then
if test "$with_dbm" != "no"
then with_dbm="yes"