diff --git a/ldap-useradmin/edit_group.cgi b/ldap-useradmin/edit_group.cgi
index 5de5d0bb2..04e3f951a 100755
--- a/ldap-useradmin/edit_group.cgi
+++ b/ldap-useradmin/edit_group.cgi
@@ -50,9 +50,14 @@ print "<td valign=top><input name=group size=10 value='$group'></td>\n";
 print "<td valign=top><b>$text{'gedit_gid'}</b></td>\n";
 if ($in{'new'} && $config{'next_gid'}) {
 	# Next GID comes from module config
+	while(1) {
+		$newgid = $config{'next_gid'};
+		$config{'next_gid'}++;
+		last if (!&check_uid_used($ldap, &get_group_base(),
+					  "gidNumber", $newgid));
+		}
 	print "<td valign=top><input name=gid size=10 ",
-	      "value='$config{'next_gid'}'></td>\n";
-	$config{'next_uid'}++;
+	      "value='$newgid'></td>\n";
 	&save_module_config();
 	}
 elsif ($in{'new'}) {
diff --git a/ldap-useradmin/edit_user.cgi b/ldap-useradmin/edit_user.cgi
index d229f92e5..1f8e22ad6 100755
--- a/ldap-useradmin/edit_user.cgi
+++ b/ldap-useradmin/edit_user.cgi
@@ -116,8 +116,12 @@ print "<td><b>$text{'uid'}</b></td>\n";
 if ($in{'new'}) {
 	# Find the first free UID above the base
 	if ($config{'next_uid'}) {
-		$newuid = $config{'next_uid'};
-		$config{'next_uid'}++;
+		while(1) {
+			$newuid = $config{'next_uid'};
+			$config{'next_uid'}++;
+			last if (!&check_uid_used($ldap, &get_user_base(),
+						  "uidNumber", $newuid));
+			}
 		&save_module_config();
 		}
 	else {
diff --git a/ldap-useradmin/ldap-useradmin-lib.pl b/ldap-useradmin/ldap-useradmin-lib.pl
index a29ba1b57..36395f65a 100644
--- a/ldap-useradmin/ldap-useradmin-lib.pl
+++ b/ldap-useradmin/ldap-useradmin-lib.pl
@@ -1137,5 +1137,15 @@ $string =~ s/
 return $string;
 }
 
+# check_uid_used(&ldap, base, name, id)_
+# Returns 1 if a user or group can be found with the given uid or gid
+sub check_uid_used
+{
+local ($ldap, $base, $name, $id) = @_;
+local $rv = $ldap->search('base' => $base,
+			  'filter' => "($name=$id)");
+return $rv->count ? 1 : 0;
+}
+
 1;