Canadian smartphone maker BlackBerry, formerly known as Research in Motion (RIM), feels very confident about its newest smartphones, especially the BlackBerry Q10.

The company jumped to its highest level in more than a month, after BlackBerry CEO Thorsten Heins said he expects the new Q10 smartphone to sell "tens of millions" of units.

"We have very, very good first signs already after the launch in the UK," Heins told Bloomberg on Thursday, April 29, referring to the new QWERTY smartphone running on BlackBerry 10 OS. "This is going into the installed base of more than 70 million BlackBerry users so we have quite some expectations. We expect several tens of millions of units."

The company's shares climbed 3.9 percent to $15.61 at the close in New York, hitting the highest price since March 21. Overall, the stock rose 32 percent this year on the hope that the new BlackBerry 10 lineup can help stage a powerful comeback for the Canadian tech giant.

BlackBerry is betting on a wave of upgrade buying from BlackBerry fans who prefer the familiar physical keyboard to boost Q10 sales and help refuel revenue growth. The other BB10 OS smartphone, the touch-screen BlackBerry Z10, sold a million units in the first quarter ending on March 2, falling in line with analyst estimates. The company's stock, however, suffered volatility in the past few weeks following reports of sluggish demand for the Z10.

According to New York-based Jefferies Group LLC (JEF) analyst Peter Misek, in the UK the department store Selfridges and outlets of Carphone Warehouse (CPW) sold out of the BlackBerry Q10 quickly.

"Salespeople were well-versed on the device and there was more apparent buzz versus the Z10 launch," said Misek, as cited by Bloomberg.

Earlier this month, on April 12, BlackBerry said it would ask security regulators to look into a report from Detwiler Fenton & Co., which stated that new BlackBerry smartphones have high return rates. BlackBerry said this "false" information was potentially a deliberate attempt to manipulate its stock price. The company asked for both the U.S. Securities and Exchange Commission and the Ontario Securities Commission to investigate that report.

Data for BlackBerry and Verizon Wireless, one of its U.S. carrier partners, shows that return rates for the BlackBerry Z10 are "completely in line" with industry standards and "better than previous BlackBerry launches were, so the quality speaks for itself," explained Heins.