If your son is a full-time student, you can claim him on your taxes, no matter how much her earns from his job.
If he is NOT a full-time student, you can claim him if he makes less than $3,100 in 2004.
His income is never included on your return - he must file his own return, if a return is needed - even if just to claim a refund of withholding.
If this does not answer your question, or raises other questions, please let me know.
Public Accountant , Tax Preparer
30+ years in Public Accounting and Tax Preparation