suppressing line wrap after a span element?

I am using span element to render a text editing caret and would 
like to know if there is any way to prevent the browser from 
wrapping the line immediately after the span element?

This problem manifests itself on IE and Firefox but not Opera.

p.s. a better long term solution for carets would be for there to be 
a DOM interface to getting, setting and removing the caret, but in 
the meantime, a span element does a fair approximation.

  Dave Raggett <dsr@w3.org> http://www.w3.org/People/Raggett