diff --git a/ag/include/clan_fights.inc.php b/ag/include/clan_fights.inc.php
index f578ed5..cc63ec1 100644
--- a/ag/include/clan_fights.inc.php
+++ b/ag/include/clan_fights.inc.php
@@ -65,8 +65,6 @@ function challengeClan(array $user, $clanid, $anzahl = 5, $type = DAVY_BACK_FIGH
 		return 'Einer der Clans erfüllt die Anforderungen an Clanfights nichtmehr (wahrscheinlich zu wenig Members)!';
 	}
 
-
-
 	if(!semaphoreUP($ressource_clan1)) {
 		return 'Fehler beim Verarbeiten der Anfrage für  \'' . $clan['clanname'] . '\' versuche es bitte nochmal! ';
 	}
@@ -78,7 +76,9 @@ function challengeClan(array $user, $clanid, $anzahl = 5, $type = DAVY_BACK_FIGH
 
 	// okay we have both semaphores :)
 
-	$clan_challenges_my_clan = getOpenChallengeRequestCount($user['clan']) + count(getOpenChallengeIDs($user['clan']));
+	$myOpenChallengeIDs = getOpenChallengeIDs($user['clan']);
+
+	$clan_challenges_my_clan = getOpenChallengeRequestCount($user['clan']) + count($myOpenChallengeIDs);
 	$clan_challenges_oth_clan = getOpenChallengeRequestCount($clanid) + count(getOpenChallengeIDs($clanid));
 
 	if($clan_challenges_my_clan >= MAX_OPEN_REQUESTS) {
@@ -93,6 +93,17 @@ function challengeClan(array $user, $clanid, $anzahl = 5, $type = DAVY_BACK_FIGH
 		return 'Der Clan "'.$oclan['clanname'].'" hat schon die maximale Anzahl von Herausforderungen offen!';
 	}
 
+	// check if we have a open challenge with this clan ...
+	foreach ($myOpenChallengeIDs as $clan_challenge_id) {
+		$challenge_clans = getParticipatingClanIDs($clan_challenge_id);
+		if(in_array($user['clan'],$challenge_clans) && in_array($clanid,$challenge_clans)) {
+			semaphoreDown($ressource_clan1); // free the previously reserved semaphore!
+			semaphoreDown($ressource_clan2); // free the previously reserved semaphore!
+			return 'Der Clan kann derzeit nicht herausgefordert werden, da noch ein offener Clan-Fight mit diesem Clan besteht!';
+		}
+	}
+
+
 	// check if both clans have already been challengeing each other since 24h?
 	$sql = 'SELECT count(*) as anzahl FROM clan_challenge_requests WHERE clan_requester IN ('.$user['clan'].', '.$clanid.') AND clan_challenged IN ('.$user['clan'].', '.$clanid.') AND  challenged_time > TIMESTAMPADD(day, -1, now())';
 	$qry = mysql_query($sql);