Do not hard code imgs especially from KM theme (use cSS instead).

Forgotten be part of  9a710678

bt5/erp5_discussion/SkinTemplateItem/portal_skins/erp5_discussion/ERP5Site_viewDiscussionThreadGadget/your_add_new_thread_link.xml

@@ -147,7 +147,7 @@
             <key> <string>_text</string> </key>
             <value> <string encoding="cdata"><![CDATA[
 
-python: \'<a class="bt-small" style="width:100px;" href="%s/discussion_thread_module/DiscussionThreadModule_viewCreateNewDiscussionThreadDialog?cancel_url=%s"><span><img src="km_img/icon-add.png" alt="+"/>Post message</span></a>\' %(here.getWebSiteValue().absolute_url(), here.absolute_url())
+python: \'<a class="bt-small" style="width:100px;" href="%s/discussion_thread_module/DiscussionThreadModule_viewCreateNewDiscussionThreadDialog?cancel_url=%s"><span>Post message</span></a>\' %(here.getWebSiteValue().absolute_url(), here.absolute_url())
 
 ]]></string> </value>
         </item>

bt5/erp5_discussion/bt/revision

-145
+146
\ No newline at end of file