There are two main pieces to a CV joint (forget about the cage and the ball 
bearings themselves for a minute).  
1) The splined chunk that fits on to the drive shaft (technically 
   referred to as the 'inner bit');
2) The larger, kinda disc shaped chunk that you bolt to the wheel or 
   transmission with those 6 allen-head bolts (technical term: the 'outer 
   bit').

Six ball bearings run between them.  As Bob has pointed out in one of his 
sermonettes, it's a Good Idea to keep track of which ball bearing belongs 
in which position.  It sounds like you didn't do that, but while it's a 
Good Idea, it's not the source of your problem, but it may reduce the 
overall life of the CVs if you didn't follow Bob's Word.

Here's your problem:  Notice how it seems that the inner and outer bits 
have six deep grooves machined in them for the ball bearings to move back 
and forth in?  Well, only every other one of the possible matching pairs 
will work.  If you've put your joint back together with the inner and 
outer bits mis-matched, the joint will sieze.  Believe me, I've been there.
 
This is difficult to explain, but look at your CV joint, and imagine that 
the ball bearings are positioned on a clock face, with the end of the 
drive shaft being at the centre of the face.  You'll have ball bearings 
positioned at noon, 2, 4, 6, 8, and 10 o'clock (six bearings).  If your 
joint siezes on re-assembly, take the joint apart again, and rotate the 
outer bit so that the groove for the outer bit's 12 o'clock bearing now 
sits over the inner bit's groove for the 2 o'clock bearing.  Reassemble 
with this new orientation.  The joint should allow the inner and outer 
bits to move in all directions except rotationally wrt the driveshaft.  

This is all assuming you can actually get the damn thing apart again.  If 
this CV joint has been used before, it should be loose enough to get 
apart without much problem.  Be sure to use CV joint grease when 
reassembling.  Removing the joint from the shaft will make life easier, 
and I'd argue that it's worth your while to slap new boots on while 
you're into the CVs anyway--they're like $15.00 a piece, and new ones 
will protect your investment in time and $$$.

Tobin   

------------------------------------------------------------------------------
Tobin T. Copley                  Currently              =============  
(604) 689-2660                    Occupationally       /_| |__||__| :| putta
tobin@freenet.vancouver.bc.ca      Challenged!        O|             | putta
                                                       '-()-------()-' 
Circum-continental USA, Mexico, Canada 15,000 miles... '76 VW Camper! (Mango)