Currently the packages:imports command only works on resolved/active bundles.
If the bundle has missing constraints and is in installed state it just prints out:
karaf@root> packages:imports 140
<bundlename> (140): No active imported packages.
It would be better if it:
a) say that the command does not work on installed state
or even better
b) print out what packages are not resolving.
The information might be obtained from the osgi:headers command, but this is an additional step to take and not very intuitive.