I don't believe you can and also it takes a long time. If you notice how long it takes the people at MCP to update that's how long it'll take you also. Just stay on 1.0.0 no since of updating since their minor fixes or updates.
Unless Notch re-encrypted the code when making a snapshot, then wouldn't only the things that were added look like func_1123123123123_sdasdasdasd? So shouldn't you be able to easily update your mods?