ms_galaxys

i recently rooted my samsung galaxy s i9000 and installed busybox. i know it is rooted because after i did it and my phone rebooted superuser permissions was automatically installed installed. i also checked whether busybox was installed and whether my phone was rooted using root checker and they are both successful. however wen i open up titanium backup an error message says that it could "not acquire root privileges" and to verify that my ROM is rooted and includes Busybox. the external storage and backup memory is fine. its just the root access that has failed. please help! thankyou in advance