[Tilesathome] Clients seem to have stopped

[pml1 at wuzel.de]

Looking at munin and in the list of recently uploaded requests, it seems as if 
a lot of clients have stopped working.

After looking around a bit, here is a wild guess:
- a lot of blank sea tiles have been requested including layer caption
- there is no caption on these tiles, so no zipfile is generated
- no zipfile for caption is uploaded, so the request stays active
- the client has to many active requests and so does not get new requests

But this is just guessing.

Peter