@@ -130,11 +130,11 @@
 	 (num-running             (cdb:remote-run db:get-count-tests-running #f))
 	 (num-running-in-jobgroup (cdb:remote-run db:get-count-tests-running-in-jobgroup #f jobgroup))
 	 (max-concurrent-jobs     (let ((mcj (config-lookup *configdat* "setup"     "max_concurrent_jobs")))
 				    (if (and mcj (string->number mcj))
 					(string->number mcj)
-					#f)))
+					1)))
 	 (job-group-limit         (config-lookup *configdat* "jobgroups" jobgroup)))
     (if (not (eq? *last-num-running-tests* num-running))
 	(begin
 	  (debug:print 2 "max-concurrent-jobs: " max-concurrent-jobs ", num-running: " num-running)
 	  (set! *last-num-running-tests* num-running)))