This paper presents an empirical task-based user evaluation, which was carried out for the purpose of assessing the subjective QoS of a mobile multimedia web service in a real multi-access network environment comprising of WLAN and GPRS networks and automatic mobility management with Mobile IP. Subjective quality ratings were collected from 20 test users to obtain a distribution representing the service quality experienced by the subjects. The obtained results show that even though the service usability in GPRS domain was barely satisfactory, this type of automatic utilization of multiple access networks with some enhancements can be considered as a potential access method for mobile services.