In general, if you lie on your resume, you cannot later sue your employer claiming you were wronged. For example, if you were terminated for cause from a prior position and fail to disclose it you lose your right to sue your employer. This is called the "after-acquired evidence" theory or doctrine.
A few other examples that constitute lying:
Not putting a former employer on a resume
Making false statements about education, experience or holding professional licenses
Concealing or failing to reveal a former felony conviction, and
Making up a college degree during an interview.
EDIT: Someone asked for a source. Here are two:
http://employment.findlaw.com/employment/employment-employee...
and
http://en.wikipedia.org/wiki/Disparate_treatment#After-Acqui...
Many more available from Google:
Extract from the Disparate treatment entry on wikipedia:
If an employer takes an adverse employment action against an employee for a discriminatory reason and later discovers a legitimate reason which it can prove would have led it to take the same action, the employer is still liable for the discrimination, but the relief that the employee can recover may be limited. McKennon v. Nashville Banner Publishing Co., 513 U.S. 352 (1995). In general, the employee is not entitled to reinstatement or front pay, and the back pay liability period is limited to the time between the occurrence of the discriminatory act and the date the misconduct justifying the job action is discovered. McKennon, 513 U.S. at 361-62.