Same LAC for 2G/3G or GSM/UMTS

[Optimustron]

Somebody knows how to set the same LAC for 2G and 3G with the same CORE, in this case HUAWEI, and differente types of providers for BTS, E*******, and NODE B, HUAWEI.

I tryied but when I issued the command ADD LAIGCI for a LAC that exist in 3G it gives me the following answer:
This record already exists in the 3G LAI Information table [ADD LAISAI]. Please enter a new value

I heard that is possible to use the same LAC for GSM/UMTS, can somebody help me please?