Salesforce.com (CRM) agreed Tuesday to acquire ExactTarget (ET) for roughly $2.5 billion, as the maker of business software expands its digital marketing portfolio.

Salesforce is buying the company for $33.75 a share in cash, a 53% premium over Monday’s closing price. The deal is expected to close by late July.

Shares of ExactTarget soared 52.8% to $33.77 in pre-market trading.

ExactTarget was founded in 2000 and makes software for businesses looking to market to their customers using the Web, email, mobile and social media.

Salesforce, which has expanded its offerings beyond helping businesses automate their sales process, said it plans to combine ExactTarget’s digital marketing with its own social and mobile services for sales, service and marketing

During a conference call with analysts Tuesday morning, Salesforce Chairman and Chief Executive Marc Benioff said the company will take an M&A “vacation” for about 12 to 18 months.

The company also announced revisions to its financial outlook. Salesforce lowered its forecast for adjusted per-share earnings in the second quarter to between six cents and seven cents, down from 11 cents to 12 cents. Quarterly revenue was left unchanged.

For the full year, adjusted earnings are expected to fall between 31 cents and 33 cents a share, compared to a previous view of 47 cents to 49 cents. Revenue is projected to be $3.955 billion to $4 billion, up from $3.84 billion to $3.88 billion.

Salesforce was trading 3.5% lower pre-market at $39.60. The stock was down 2.3% on the year as of Monday’s close.

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