Jammed Shifter 2003 manual 5 spd
 

I have a 2003 with a manual 5 spd.
"Out of the blue" the shifter jams making it damn near impossible to disengage from 5th gear or reverse, or conversly, get it into 5th gear or reverse from 1st,2nd,3rd or 4th.

I've read a few posts about jamming shift linkages but have not seen any resolution of this problem.

Is there a known common problem that is fixable at a reasonable cost?