Only certain versions of IOS support the cme-srst feature license. We recently ran into a problem with a group of new 3945 IS Routers we installed. We found that when running the show license detail cme-srst command that we also were getting the "% Error: No license for cme-srst found - License feature not found" message. After reading some Cisco documentation we found that there were certain IOS releases we needed to be at to support the cme-srst feature license. We upgraded one router from 15.0(1)M3 to 15.1(4)M3 and then found that we had the feature license and were able to accept the EULA. Be wary however, we found out yesterday that the Cisco documentation is incorrect. In the "Software Activation on Cisco Integrated Services Routers and Cisco Integrated Service Routers Generation 2" document it states,
"Starting with Cisco IOS Releases 15.0(1)M6, 15.1(1)T4, 15.1(2)T4, 15.1(3)T2, and 15.1(4)M, Evaluation licenses are replaced with Evaluation Right To Use licenses. Evaluation Right to Use licenses automatically become Right to Use licenses after the initial evaluation period. Follow the steps detailed in this section to activate an Evaluation Right to Use license."
We found last night, and Cisco has confirmed, that this is incorrect. We upgraded a 3945 IS router last night to IOS 15.1(2)T4 and still did not have the cme-srst feature license. Cisco tried in their lab and found the same thing. They have acknowledged that the document is incorrect. If you have a lab, test your IOS versions first to see if when you run the show license detail cme-srst command that you see something like the following:
ROUTER#sh license detail cme-srst
Feature: cme-srst Period left: 8 weeks 4 days
Index: 1 Feature: cme-srst Version: 1.0
License Type: EvalRightToUse
License State: Not in Use, EULA not accepted
Evaluation total period: 8 weeks 4 days
Evaluation period left: 8 weeks 4 days
Period used: 0 minute 0 second
License Count: 0/0 (In-use/Violation)
License Priority: None
Store Index: 7
Store Name: Built-In License Storage
Notice that this indicates that the EULA has not been accepted but that the feature does exist. Once you accept the EULA it will look something like this:
ROUTER#sh license detail cme-srst
Feature: cme-srst Period left: 8 weeks 3 days
Index: 1 Feature: cme-srst Version: 1.0
License Type: EvalRightToUse
License State: Active, In Use
Evaluation total period: 8 weeks 4 days
Evaluation period left: 8 weeks 3 days
Period used: 0 minute 22 seconds
Transition date: Apr 24 2012 17:27:13
License Count: 23/0 (In-use/Violation)
License Priority: Low
Store Index: 7
Store Name: Built-In License Storage
Notice how the 60-day evaluation has started counting down. The evaluation only starts ticking if you have the telephony-service command active on the router. Once the 60 day evaluation runs out it is an "on your honor" license type where you should have purchased licensing for cme-srst but there is no license PAK that gets installed on the router.
UCK9 license 
