[sylpheed:35232] Plugin interface version mismatch

[Fidel Mato]

Hi,

Trying to install Attachment-Tool Plug-in in 
  
  Debian 6.0.4 (squeeze) | Gnome 2.30.2
  Sylpheed version 3.0.2
  Operating System: Linux 2.6.32-5-amd64 (x86_64)
  Compiled-in features: gthread IPv6 iconv compface GnuPG OpenSSL

Got these warnings:

** Sylpheed-WARNING: Plugin interface version mismatch: plugin: 263, app: 260
** Sylpheed-WARNING: Version check failed. Skipping: /usr/lib/sylpheed/plugins/attachment_tool.so

And, of course, plug-in is not working. Some hints?
Thank You