if I were in your shoes, I would download the junction utility from MS : http://technet.microsoft.com/en-us/sysinternals/bb896768.aspx and then map your "C:\path" to say, "z:" and "c:\path2" to say, "y:". This way, you will be reducing 4 characters per item in your classpath.

set CLASS_PATH=C:\path\a\b\c;C:\path\e\f\g;....
set CLASS_PATH=%CLASS_PATH%;C:\path2\a\b\c;C:\path2\e\f\g;..

Now, your classpath will be :
set CLASS_PATH=z\a\b\c;z\e\f\g;....
set CLASS_PATH=%CLASS_PATH%;y:\a\b\c;y:\e\f\g;..

It might do more depending on your actual classpath.

If I were in your shoes, I would download the junction utility from MS : http://technet.microsoft.com/en-us/sysinternals/bb896768.aspx and then map your "C:\path" to say, "z:" and "c:\path2" to say, "y:". This way, you will be reducing 4 characters per item in your classpath.

set CLASS_PATH=C:\path\a\b\c;C:\path\e\f\g; set CLASS_PATH=%CLASS_PATH%;C:\path2\a\b\c;C:\path2\e\f\g; 

Now, your classpath will be :

set CLASS_PATH=z\a\b\c;z\e\f\g; set CLASS_PATH=%CLASS_PATH%;y:\a\b\c;y:\e\f\g; 

It might do more depending on your actual classpath.