In the original bibliography support module usage was as follows (example taken from the contextgarden wiki):
<pre detail='typing'>% engine=pdftex
\usemodule[bib]
\usemodule[bibltx]
<br/>
Another difference is the use of lists. When you define a rendering, you also define a list. However, all entries are collected in a common list tagged <tt>btx</tt>. Although you will normally configure a rendering you can still set some properties of lists, but in that case you need to prefix the list identifier. In the case of the above example this is <tt>btx:document</tt>.
=MLBIBTEX=