Synchron consume behavior

[Adrian Tarau]

I'm using ActiveMQ 3.2.2 , embedded with derby for storage, and I have a 
strange behavior when consuming messages.

I know for sure that the queue has more that 100 messages, but if I 
consume with receive() sometime(a lots of times) the result is null, 
like there are no messages. If I put receive(1000) then seems to work 
fine, even if a few times I noticed a null value even if the queue had 
items.

Anybody got some problems like that?