test_call_hold.c: fixed timing problem in test 7.6.1
test_call_hold.c: fixed timing problem in test 7.6.1

darcs-hash:20080526233300-db55f-f8542d7de321ef5da807b2e17c870e1fb86e1e43.gz

BelledonneCommunications/sofia-sip,unispeech/sofia-sip,jart/sofia-sip,xhook/sofia-sip,BelledonneCommunications/sofia-sip,xhook/sofia-sip,jart/sofia-sip,BelledonneCommunications/sofia-sip,erdincay/sofia-sip,erdincay/sofia-sip,xhook/sofia-sip,unispeech/sofia-sip,BelledonneCommunications/sofia-sip,xhook/sofia-sip,xhook/sofia-sip,unispeech/sofia-sip,erdincay/sofia-sip,unispeech/sofia-sip,jart/sofia-sip,erdincay/sofia-sip