Hi Eric, I feel your pain.
I have exactly 1 customer that is having the same problem with log pinning, and 
I can't figure out why.

-In the past, we've all seen logpinning problems when a site is running in 
rollfoward mode with large, slow TDP clients coming in over the WAN.
-There are also issues with the Windows client from 6.0.0 through 6.1.2 that 
will cause the client to "sleep" for many hours in the middle of a backup, 
which I suspect can contribute to log pinning.

But this customer is running 5.5.4 in normal mode, they upgraded all the Win 
6.0 clients, all the clients come over GigE.
And yet they have problems with the log pinning.
Go figure.

One suspect is a large 64bit SQL TDP that backs up ~300GB per day.  I'm 
suspecting him because it is 1 large object.  But SHOW LOGPIN doesn't always 
finger that guy - it varies.  (I'm beginning to wonder if the code bug is in 
SHOW LOGPIN...)

Wanda