Yes, it complies. Example: prefix 0048 added 3 times, once with priority 0 and balance share 100% and then twice more with 50% share. Any combination is allowed, just remember to always use full 100% share for entries with same priority (f.e.: when 4 prefixes use share 25% for wach one, or 40%/40%/10%/10% or any where sum is equal to 100%).
In case balance share is not working properly, please check is check-box Use load balancing in VSM->Settings->Voipswitch selected.