[collectd] Collectd compatibility issue

[Ivaylo Lenkov]

I have a cluster of many servers running Ubuntu 6.06 LTS (32 bit) with collectd 4.3.0. I had to upgrade one machine to Ubuntu 9.10 x64 which comes with collectd 4.6.3 (64 bit binary), and after that the stats coming from this machine are no longer valid (the CPU and DISK plugins). At the same time the mysql plugin seems to be working perfectly fine. 

The problem with both CPU and DISK stats is that they come either as zeros or as some off-the-chart number and this changes every hour.  The chart looks like:
   _    _    _
_|  |_|  |_|  |_

So my questions are:
1. is version 4.3.0 over-the-wire compatible with  4.6.3?

2. is 64bit pre-built ubuntu package compatible (again over the wire) with the 32bit pre-built ubuntu package?

3. How is possible some plugins (MySQL) to be working just fine, while others (CPU, DISK) to be completely wrong?

4. Any idea how to solve this without having to recompile from source the collectd on all servers?

Thanks,

Lenkov