[Typo3] How to add a function call to the bodys onLoad attribute

[Richard Downes]

Hi,
I have written an frontend plugin which needs to add a javascript 
function call to the bodys onload tag. I've spent about two weeks trying 
to figure this out.
In my php class I added the function call like this :
$GLOBALS['TSFE']->JSeventFuncCalls['onload'][$this->prefixId] = 
"myfunction();"

It is not appearing in T3_onloadWrapper(), however there are two other 
calls in there (GL_initLayers() and GL_restoreMenu("b089e2")) which are 
generated by GMenu.