Maven Perforce plugin suddenly requires a password?

In my pom.xml I have:

<scm>
    <connection>scm:perforce://path_to_my_开发者_开发百科repository</connection>
</scm>

This has worked fine until recently. Now when I build I receive the following message:

"password is required for the perforce scm plugin."

The maven documentation for the plugin does not specify a way to include a password (http://maven.apache.org/scm/perforce.html).

What is going on? How to I get past this problem?

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It turns out that the error message did not match the problem. The 'password' needed message appears to be a catch-all message when something goes wrong. We found the error was a result of a invalid dependency that was introduced. This was fixed and the prompt for the password disappeared.

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You could be using a version of the plugin which has this bug (SCM-415). This SO question has a related problem.