Hi Robert,
Have a look at Step # 7 below;
To set the Service Parameters for Cisco CallManager Extension Mobility, perform the following steps:
Procedure
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Step 1 From Cisco CallManager Administration, choose Service > Service Parameters.
The Service Parameters Configuration window displays.
Step 2 From the Server drop-down menu, choose the server that is running the Cisco Extension Mobility service.
Step 3 From the Service drop-down menu, choose Cisco Extension Mobility.
A new Service Parameters Configuration window displays.
Step 4 At the Enforce Maximum Login Time, choose True to specify a clusterwide maximum time for logins. After this time, the system automatically logs out the device.
Choosing False means that no clusterwide maximum time for logins exists.
The default value specifies False.
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Tip To set an automatic logout, you must choose True in Step 4 and also specify a system maximum login time in Step 5. Cisco CallManager then uses the automatic logout service for all logins.
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Step 5 If you specified True at the Maximum Login Time field in Step 4 of this procedure, specify the maximum login time in Hours:Minutes from 0:01 to 168:00 (1 minute to one week).
The default value specifies 8:00 (8 hours).
Step 6 At the Multi Login Behavior field, choose one of the following responses:
Multiple Logins Allowed: A user can log in to more than one device at a time.
Multiple Logins Not Allowed: The second and subsequent login attempts after a user successfully logs in once will fail.
Auto Logout: After a user logs in to a second device, the Cisco CallManager automatically logs the user out of the first device.
The default value specifies Multiple Logins Not Allowed.
Step 7 At the Alphanumeric Userid field, choose True to allow the UserID to contain alphanumeric characters. Choosing False allows the UserID to contain numeric characters only.
The default value specifies True.
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Note The Alphanumeric Userid parameter applies systemwide. You can have a mix of alphanumeric and numeric userids. The only supported Userids are those that can be entered using the alphanumeric keypad.
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Step 8 At the Remember last user logged in field, choose the default value, False.
A True setting specifies that the Extension Mobility application remembers the user ID of the last user that logged in to the phone. Use this setting in situations where individuals use their own phone on a regular basis, and no one else uses that phone. For example, if Cisco CallManager Extension Mobility is being used to enable the types of calls that are allowed from a phone, individuals using their office phone can make only internal or emergency calls. But after logging in using Cisco CallManager Extension Mobility, the user can make local, long-distance and international calls also. In this scenario, only this user regularly logs into the phone. It makes sense to set the Cisco CallManager Extension Mobility to remember the last user ID that logged in, and you would set the field to True.
In a typical hoteling scenario, where users can come into any office and use any phone on a temporary basis, you should set this parameter to False.
Step 9 Click Update.
Step 10 If Cisco CallManager displays a message that a Cisco Tomcat restart is required, click Update again.
From this doc;
http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_administration_guide_chapter09186a00801ed113.html
Hope this helps!
Rob
