Method of handling mobile station identifiers

1. A method of handling mobile station identifiers, comprising:

programming at least one network element that used entire mobile station identifiers in performing packet data session handling functions between a control element on a first network and a control element on a second network to use less than the entire mobile station identifiers in communication between the control element on the first network and the control element on the second network, the second network being different from the first network;

comparing, at the at least one network element, a partial portion of a mobile station identifier associated with the control element on the first network with a partial portion of a mobile station identifier associated with the control element on the second network; and

performing, at the at least one network element, the packet data session handling functions based on the comparing such that the at least one network element transfers a current data session of a mobile station established with the control element on the first network to the control element on the second network without performing a new signaling operation if the partial portion of the mobile station identifier associated with the control element on the first network matches the partial portion of the mobile station identifier associated with the control element on the second network,

wherein the programming programs a packet data service node or a packet control function unit, and

wherein the packet data session handling functions include at least one of handoff, dormant closure, and border cell call delivery.

2. The method of claim 1 , wherein the programming programs the at least one network element such that the network element uses a least significant 10-digits of the mobile station identifiers.

3. The method of claim 2 , wherein the at least one network element used 15-digit mobile station identifiers prior to the programming.

4. The method of claim 3 , wherein the at least one network element used 15-digit international mobile subscriber identifiers, IMSIs, prior to the programming.

5. The method of claim 1 , wherein the at least one network element used 15-digit mobile station identifiers prior to the programming.

6. The method of claim 5 , wherein the at least one network element used 15-digit international mobile subscriber identifiers, IMSIs, prior to the programming.

7. The method of claim 6 , wherein the programming programs the at least one network element to use the 10-digit mobile identification number portion of the IMSIs.

8. The method of claim 1 , further comprising:

re-programming the network element to use in the entire mobile station identifiers in performing packet data session handling functions.

9. A method of handling mobile station identifiers, comprising:

using less than an entire mobile station identifier in communication between a control element on a first network and a control element on a second network when performing packet data session handling functions between the control element on the first network and the control element on the second network, the second network being different from the first network;

comparing a partial portion of a mobile station identifier associated with the control element on the first network with a partial portion of a mobile station identifier associated with the control element on the second network; and

performing, at at least one network element, the packet data session handling functions based on the comparing such that the at least one network element transfers a current data session of a mobile station established with the control element on the first network to the control element on the second network without performing a new signaling operation if the partial portion of the mobile station identifier associated with the control element on the first network matches the partial portion of the mobile station identifier associated with the control element on the second network,

wherein the at least one network element is a packet data service node or a packet control function unit, and

wherein the packet data session handling functions include at least one of handoff, dormant closure, and border cell call delivery.

10. The method of claim 9 , wherein the using uses a least significant 10-digits of the mobile station identifiers.

11. The method of claim 10 , further comprising:

receiving a 15-digit mobile station identifier.