Jms multisite for joomla 1.2.92 remove a "PHP notice" message for Joomla 2.5 compatibility.
It is also bundled with the jms multisite patches definition 1.2.86 that:

• Add a patch for JomSocial, jomdirectory, jomestate
  This fix a problem with the Ajax call performed by theses extension that may get error due a wrong value present in JPATH_COMPONENT.
  This replace the dirname(__FILE) by JPATH_BASE.'/components/OPTION' where the option is the extension directory.
• Add JMS Tools (install) definitions for :
  - JFBChat (Joomla Facebook Chat)
  - Podcast Manager
• Add Joomla 2.5 sharing definition for:
  - JomRes