Cannot Find use for "1999" in CM 6.0.1

[richardwallot]

4 different engineers have been looking for the use of "1999". It does not show under lis usage ext or dig 1999. I could use some help finding where this is being used. We dialed it while tracing but it appeared to be trying to access an IP address. CM 6.0.1 with latest SP

Thanks,
Richard

[mburke]

We have extensions in "list uniform-dialplan" that do not show up in list usage reports however it does show on list trace so that may not be it.