xintx-ua: I don't know why it uses the cal from bsdmainutil's rather than util-linux; but it seems pretty arbitrary.
The version in util-linux appears to be a different piece of berkeley licensed code, but given that there is precisely
nothing Linux specific about cal or even vaguely systemy, I can't see why cal is in util-linux anyway.
xintx-ua: I don't know why it uses the cal from bsdmainutil's rather than util-linux; but it seems pretty arbitrary.
The version in util-linux appears to be a different piece of berkeley licensed code, but given that there is precisely
nothing Linux specific about cal or even vaguely systemy, I can't see why cal is in util-linux anyway.
Dave