NEW YORK (Reuters) - A former Sprint Nextel (S.N) executive has sued the No. 3 mobile service provider for wrongful dismissal, saying that she was fired after claiming Nextel Partners artificially pumped up sales data prior to its acquisition by Sprint, according to the Wall Street Journal.

Joanne Marie Toledo Hamm, who oversaw Sprint's integration of Nextel Partners in Hawaii, sued Sprint Nextel on Thursday in First Circuit Court in Honolulu. The allegations of fraudulent sales reporting at Nextel Partners could raise questions about whether Sprint overpaid for Nextel in 2006, the paper said in a story published on its Web site on Friday.

Nextel Partners was an affiliate of Nextel Communications Inc, which Sprint acquired in 2005.

The suit alleges that employees of Nextel Partners ordered phones for customers without their consent to inflate sales numbers, which improved the appearance of Partners' results and in turn increased the price that Sprint eventually paid to acquire it.

To mask the fraudulent sales, the suit alleges, the phones were essentially shipped from one part of Nextel Partners' warehouse to another, and credits were issued to cover the cost of the equipment and services on customers' bills.

Hamm alleged the practice extended beyond Hawaii, the paper said. In the lawsuit, she claimed she completed an investigation into the activity in late 2006 and brought it to the attention of her supervisor, who “actively discouraged” her from doing anything about the issue.

Sprint spokeswoman Leigh Horner told Reuters on Friday Hamm's dismissal “stems from multiple complaints and her behavior and violations of Sprint Nextel's code of conduct.”

(Reporting by Franklin Paul and Ritsuko Ando; Editing by Gary Hill)