I'm going to bed, cause i've been up for like 24 hours, but my installers aren't locked or anything and they're just winrar SFX's - you should be able to use winrar to incorporate whatever theme you want, prathapml. I've never worked with Thunderbird themes before, I'll have to look into it, but you should be able to add files, scripts, and registry entries with no problem via the latest version of winrar. I'll do more work on it later.