If you're really no more than 1 inch short you should be fine.  You should be able to "cheat" just a bit with the thru holes for the sail attachment, moving them a bit closer to the spar ends.  You can also be creative in how you do your sail lashing in order to minimize length given up to knots, and still have the ability to rig the sail plenty tight.  Even so, just to be sure, if you already have your sail you might lay it out against the spar to be sure things will fit.

Ian,

I have yet to see any sailboat where a less than 1% error in a spar's length would cause a problem. If you're really worried, just screw an eyebolt into the end and run your line through that (but do wrap a piece of fiberglass around the end of the spar to support the new side loads).

If you do scarf, put a large-ish plug in the middle of the spar, not at the ends. But again, I think you're fine as-is.

Laszlo

Ninja'ed by Bubblehead  

Double Amen! as to checking the spars to the actual sails before you do anything to the sticks.  As the wise heads above have noted, you're probably okay at to having plenty of stick to work with.  Stretching the head and foot of the sail out against their respective spars will allow you to determine where locate the holes so as to get good tension and allow for a bit of stretch over time.

.....Michael