Cell selection Issue

Hello All,

We are facing a problem in our 2G+3G network that MS enters cell selection mode after a normal 3G to 2G cell reselection; under good 2G radio conditions like mostly C1/C2 is more than 20
There are 3 scenerios in which we can categorise this behaviour:
1. MS enters cell selection mode immediately after 3G to 2G cell reselection, after correctly recieving the sys Info Type 3, BA list, mode reports indicating correct decoding of BS list & other parameters.
2. MS enters cell selection mode after max_retrans & T3126 expiry (Rach attempts are being sent for LU process after 3G to 2G reselection)
3. MS enters cell selection mode after successful LU process completion following 3G to 2G reselection
In all these scenerios, RxLev of serving & neighbor cells are found good after 3G to 2G reselection but still MS triggers cell selection mode as per TEMS mode reports, which normally takes 4-5 secs
Any ideas regarding this issue ll be highly appreciated
thanks in advance!