addwppack + "Version 2.0 is not compatible version"

when

stsadm.exe -o addwppack-name Web_Part_Pack_name

got:

"Version 2.0 is not compatible version", failed to deploy .cab file.

here is the solution:

create a file named stsadm.exe.config:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<startup>
<supportedRuntime version="v2.0.50727" /> <!-- update the version # once .Net v2.0 is released -->
<supportedRuntime version="v1.1.4322" /> <!-- this is the version number for .Net v1.1 -->
</startup>
</configuration>

copy it to the same folder where stsadm.exe located.

that's it.