Shares of Office Depot (ODP) and OfficeMax (OMX) are up Wednesday after the office supply retailers backed their 2012 earnings forecasts,  countering worries about an economic slowdown highlighted by FedEx's (FDX) earnings forecast reduction.

Office Depot, based in Boca Raton, Fla., expects earnings of $125 million to $135 million in 2012, excluding special items, interest and taxes, along with free cash flow of $80 million to $100  million.

OfficeMax, based in Naperville, Ill., is expecting third-quarter sales to be flat or slightly higher than a year earlier, with adjusted operating income of 2.3%, in-line with the year-ago period. Sales for the year will be little changed from 2011, while adjusted operating income margin will be 1.7%, around the level where it was last year.

Investors were bracing themselves for much worse news from the chains, which are sensitive to swings in economic confidence. Yesterday, Office Depot reported a worse-than-expected quarterly loss amid soft demand in both the U.S. and Europe. The picture seems better at OfficeMax, which last month reinstated its dividend after a three-year absence as its business stabilized. Shareholder Neuberger Berman's call to return more capital to investors certainly played a role in the decision as well.

Office Depot and OfficeMax sell mundane products like envelopes and toner cartridges, which companies need to buy in good times and bad. The fact that these chains don't see things getting worse is good news. As consumer confidence continues to rise, small businesses may be more willing to make investments in capital equipment, such as laptops. Wall Street sees better times ahead for these companies. The average 52-week price target for Office Depot is $2.89, an increase of more than 60% from where it currently trades. OfficeMax is expected to hit $7.86, up more than 32%.

The earnings miss at FedEx was not a surprise because rival UPS (UPS) posted similar results. Shippers are bypassing express delivery for cheaper, slower options. There are reasons, though, to think that the trend won't last. First, consumers are showing signs of resilience ahead of the release of the iPhone 5, perhaps the most eagerly anticipated device in years. If consumer confidence doesn't falter, the holiday season should be decent, which would be good for FedEx, which recently reported earnings that lagged Wall Street.

Jonathan Berr does not own shares of the listed stocks. Follow him on Twitter@jdberr.