Yes, paraHO, we discussed this problem earlier 🙂
Dear, RASH! I heard about border gateway in relationship GPRS only. How will you intend to use this network element in CS-network?
As to HPLMN searching timer, then it is useless in your case (when Visited PLMN is other country PLMN). MS take HPLMN timer in account only in its Home country.
There is an inter-MSC handover – not inter-PLMN. The cell reselection procedure is applied only to cells which belong to selected PLMN (i.e. MS will check MCC-MNC this cell before using it as cell reselection candidate).
with BR, Pan.