My favorite wild fruit jam is made from the Thimble berry using the low sugar recepies found in the pectin boxes. The seeds can be annoying but these can be moderated somewhat with the use of a food mill prior to making the jam.
As an aside, in mid to late september the black elderberries one sometime finds on the back roads of E. Washington will be ready to pick. Makes great jam as well. (use a food mill for these also). A tip about these berries: when picking black elderberries, only pick the bunches/clumps with very 'black' stems as these are the ones that will be ripe and ready for harvest. If you pick them before the stems are black, even though they may look like they are ripe (usally around late Aug or Early Sept) they are not! Trust me, the ones with the black stems make the best jam/jelly. (or wine? never tried that!) Easiest way to seperate the elderberry from the stems is to freeze the entire clump and then simply knock the frozen berries from the stems. works like a charm! Good luck!