not sure if this is related, but I did have issues once which, after many hours of frustration, I discovered stemmed from my use of Storable which exports the methods store & retrieve. My module was a subclass of another which used the method store somewhere.. I wasn't even aware of it.. Anyway Storable was overriding the store method and causing some really weird errors. The solution of course was quite simple..

use Storable();
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as opposed to

use Storable;
[download]