Maybe you are not doing it right...
You just open the JAR file with winrar, then open MANIFEST with notepad and add the line
MIDlet-Touch-Support: True
this is how it looks,
Example with bejeweled:
Manifest-Version: 1.0
MIDlet-Name: Bejeweled
MIDlet-Version: 4.14.78
MIDlet-Vendor: Electronic Arts
MIDlet-1: Bejeweled, icon.png, Bejeweled
MicroEdition-Profile: MIDP-2.0
MicroEdition-Configuration: CLDC-1.1
MIDlet-Icon: icon.png
MIDlet-Description: Bejeweled by Electronic Arts, Inc.
MIDlet-Data-Size: 2048
MIDxlet-Network: N
MIDlet-Touch-Support: True
After you add it there. save the changes.
Then after all this, zip all the files again, in zip format.
then... you have to modify the file extension by yourself.
if u cannot see the file extension ".zip" then in the same window, go to:
Tools------ Folder Options...----- Click the tab "View". Now .. under Hidden files and folders... search for " Hide extensions for known files type" and unmark it. Click OK.
Now you should be able to see the .zip extension "game.zip"
Now you have to rename that "game.zip" to "game.jar" to rename it just select the game and press F2, or u can also do right click and on the game and click rename, then just modify the ".zip" for the ".jar"
Hope this is more clear for you
Happy New Year.