The H1-B rules say
That an employee can be on leave, sick leave, vacation or strike. Or in other words - your rights as an employee are in no way different than those of ANY American employee. To put it to the extreme - you may enter the US on an H1-B visa, get hired and never work a day and you haven't done anything wrong. Also remember that the INS (or whatever they are called now) has NO info from the IRS and again by law are not allowed to obtain any. Enjoy your vacation.
