ie:menu tag?

I am working with an accounting package that has recently had a web front end component developed for it which uses asp.net to generate pages from data held within.

One of the options it provides is to generate a drop down menu which in the source appears as an ie:menu tag.

I have tried googling for information but think google must strip out the : and search for ie menu even when its in quotes so was wondering if anyone here could tell me anything about the tag? Is it a standard part of ie or something added in one of the dll's that come with the web front end for this package.

Hope someone has some information,

-KM-