Using StringItem as a placeholder in J2ME: OutOfMemory error on k750

I’ve been using the following:

stringItem = new StringItem(null,null, Item.PLAIN);

to indicate a placeholder for a string in a form on a J2ME application, debugged using the Wireless Toolkit emulator provided with NetBeans. This is perfectly valid w.r.t the stringitem API. 

 All was fine until deploying it onto an  actual device, namely a SE k750, where I was getting spurious OutOfMemory exceptions. Debugging and stepping through the code, it seemed when you tried to apply a label or text to the placeholder stringItem using setText() or setLabel(), you got an OutOfMemory exception. So instead I used:

stringItem = new StringItem(null,"", Item.PLAIN);

and the problem seems to have disappeared. Not sure why this is the case, but I thought I’d post it for future reference!