Eric Auchard– Eric Auchard is a Reuters columnist. The opinions expressed are his own –

Research in Motion officials do their best not to laugh when asked if they fear the rise of a BlackBerry-killer, some theoretical device that does everything its coveted e-mail phone does, only better.

But BlackBerry’s biggest threat may come from itself. As the company’s latest quarterly results suggest, there is a gulf between its pricey corporate phones and price-sensitive consumer models that are cutting into margins.

When a loyal Research in Motion (RIM) customer such as a corporate IT manager discovers he’s paying more than twice the price at work that his the 16-year-old daughter is paying at retail, he feels ripped off. That in a nutshell is the crisis RIM faces.

Of course, RIM’s crown jewel remain its corporate business. Its franchise there stems from the thousands of company network managers who rely exclusively on RIM’s e-mail management software to ensure corporate communications are securely delivered to their intended recipients. Companies pay a premium for this reliability. Those investments lock customers into BlackBerry services and prevent other competitors from breaking in. However, this is changing.