Apple Inc's new iPhone, already racking up blockbuster sales with consumers, appears to be making small but steady inroads into the coveted US corporate market dominated by Research in Motion Ltd's BlackBerry.

While most companies are unwilling to abandon their trusted BlackBerries, analysts say a grassroots movement may be taking place among employees - particularly at small and mid-size companies - who have bought their own iPhone and are convincing their employers to support it.

"I see very few companies turning off BlackBerries," said Jack Gold, founder of research firm J.Gold Associates. "I see more companies turning on support for the iPhone."