packages appear in apt cache and synaptic but have no sources?

[RageLtMan]

While trying to figure out why remastersys wont let me build a live CD of my OS, i ran into something interesting. I have a package installed with the source listed as ubuntu\Unknown in synaptic. Apt cache search reveals the package as well (libghc6-edison) but apt-get cannot install or even see it - "E: Couldn't find package libghc6-edison"

Any ideas how to clear this out? it also caused update-xapian-apt to crash out.