[opencms-dev] Problem updating resource property

[gnorrus at libero.it]

Hi

I'm trying to update a resource programmatically

I create a CmsProperty object and then I lock the resource, I use method 
writePropertyObject to update resource, finally I unlock it.

I get error:
Error locking resource with mode "temporary exclusive" (if I use 
lockremporarx) or Error locking resource with mode "exclusive"

What does it mean?

thanks