cannot use left alt key for @ etc in x

[vasco figueiredo <vasco_f@netcabo.pt>]

hi there

after installing debian it worked fine but after upgrading some 
package(s) (don't no which) it stopped working

in console(tty1-6) everything works fine but not in gnome-terminal 
mozilla etc

in gnome-terminal both alt keys do the same

this a pt keyboard deadkeys work fine

thanx for any help