#2 attachments not working

[Roccog]

Both with intouch 2.2 (dev) and inTouch 2.1 when I compose a new mail message, I can't add a new attachment: clicking on "Attach File" has no effect.
Other sympthoms:
- after clicking on "Attach File" the CPU usage of the browser goes very high (at least on Firefox);
- on Internet Explorer, sometimes the attachments work (open the dialog to ask for the file to upload), but most of time it does not work;
- sometimes it works when double-clicking
Test enviroment:
- client and server on Windows Vista
- jdk 1.6.0_12
- tomcat 6.0.16
- firefox 3.0.6
- internet explorer 7