Is this legal?

Hi All,

I have resigned last Monday (4/15). I have told HR that my last day with my current company was 4/30 (Tuesday), they did not object. Instead they asked which date would be my last day in office - since they may need to cut all my computer access, also to finish exit interview, etc.
 
You may wonder why I did not make 4/26 as my last day in company? The main reason, as explained in my old post before, is to guarantee that I would get last year's bonus. The bonus has not shown up yet by today.... Our company's policy is that one needs to be an active employee by the time the bonus is paid out. This is the link to the last post:

http://bbs.wenxuecity.com/career/461663.html
 
I want to make 4/26 (Friday) as my last day in office. Then I will take off on 4/29 and 4/30 - our company allows employees to take off for personal business, and also to use one's floating holiday (since I have been worked for current company for 4 months, I have earned some floating holidays). This means that I will be still paid for 4/29 and 4/30, but may not have other benefits such as medical.

Regardless, I have to start my new job on 4/29. This means I will start working for the new company without officially exiting current company.

My question is if this is acceptable by law?  I am a Green Card holder and do not need any sponsorship.

Thanks a lot for help,