Despite posting double-digit growth in sales and profit late Wednesday, shares in J2 Global Communications Inc. plunged more than 20 percent Thursday morning after investors showed they were underwhelmed by the company’s third-quarter results.

J2 reported net income for the quarter of $18 million, (35 cents per share), a 41 percent improvement from the same period a year earlier.

Revenue for the Los Angeles-based Internet voice and fax services provider rose 21 percent to just more than $55 million, less than the company’s own forecast of $56 million to $57 million.

J2 added that it expects fourth-quarter sales to rise to $56 million to $58 million.

Shares in JS slipped 22 percent, or $6.93 per share, to $24 in morning trading Thursday the biggest decline for the company in more than two years.