OJS allows the use of HTML in article abstracts, and assumes that when you use < and > characters you're typing in HTML. To use those characters, either use < in place of < and > in place of > or, better yet, make use of the TinyMCE plugin. See "System Plugins" in the Journal Manager's interface.
Don't miss the First International PKP Scholarly Publishing Conference
July 11 - 13, 2007, Vancouver, BC, Canada