How to remove HomeAsUpButton arrow from ActionBar Sherlock when ActionView for Search is installed?

Question

I know how to erase the back arrow in a normal situation using the Sherlock action bar. My problem is that I cannot erase the back arrow when it appears in a search situation, with CollapsibleSearch.

I tried using getSupportActionBar().setDisplayHomeAsUpEnabled(false); in my onMenuItemActionExpand(MenuItem item) callback method without any results.

Thanks!