Due to the high request, I took 20 minutes of my time and updated the Phoenix Protector, bringing it to the version 1.6. The only addition to this version is the possibility to re-sign assemblies obfuscated by the Phoenix Protector.
The reason why this wasn’t possible in past version of the Phoenix Protector is that the space for the signature was removed from the assembly and the “sn.exe” tool provided by Microsoft isn’t able to re-create that space.
Now, it is possible to tell the Phoenix Protector from the options whether to remove or not the Strong Name Signature when obfuscating an assembly:

By default the Strong Name Signature is not removed.
After obfuscating anassembly, just use to re-sign the “sn.exe” tool this way:
sn.exe -R assembly.exe your_sns.pfx