[mina] DIRMINA-165 revisited

[Joshua Portway]

Hi,
	I've been looking at the code submitted for this bug (to allow the  
creating of read-only buffers and buffer slices) and reading the  
comments, and I'm not sure I understand why the submitted patch is  
considered "dangerous". Trustin advises that all the methods assert  
that every buffer involved is not pooled, but I'm not sure why this  
should be - presumably, assuming that any derived buffers maintain a  
reference to their parent buffer, the parent buffer won't be returned  
to the pool until all derived buffers have been released, and  
therefore released it in turn. Am I missing something here ?

        josh