and a clear violation of Tomboy's license.Notice license and copyright statements are two separate issues. AFAIK LGPL doesn't explicitly require that a license notice is preserved mixing code with other licenses like the BSD license does, but I could be mistaken. Any advice on this from -legal?
If it's not your code, and the licence does not give you explicit permission, then you can't change the licence and shouldn't remove the licence note.
Note that the GPLs fall in this category!The way you "change the licence" with this sort of code is by licencing your code with a compatible licence. The licence for the resulting combined work is the "Venn Intersect" of the two licences. If there's no intersect, then you can't distribute.
For an example, if a program has three authors, one of whom uses BSD, the second uses "LGPL 2.1 or later" and the third uses "GPL 3" then the Venn Intersect is GPL 3, which is the licence that applies to the work as a whole. However, any recipient is at full liberty to strip out parts of the work, and use whatever licence the author granted.
Cheers, Wol -- Anthony W. Youngman - anthony@thewolery.demon.co.uk