S7-400 Online blocks when connected via Slot 0

[StefanHasensperling]

While making some tests with various S7-400 (CPU414-3DP on Slot 3 and an Ethernet CP443-1 on Slot 5).
I observed the following. the PLC accepts connections via Ethernet not only on Rack 0 Slot 3, but also on Rack 0 Slot 0. The interesting thing is, that one can List the online blocks on Slot 0 and there are event some SDBs in the range of 1003 to 1012, but NOT the blocks that are loaded in the CPU. The Blocks of the CPU are only listed when connected to Slot 3 on the PLC.

From what i understand the Blocks 1000 and above are configured connections and Profibus Connections. I find it interesting that something is responding on Slot0 and does have System Blocks. Does anybody know as to why that is, and also what the content of the SDB's is?

Here i Uploaded the Binaries for the blocks i found online:
Online Blocks form S7-400 Slot 0.zip