You have to hand it to Tellabs (NASDAQ:TLAB) -- they work fast.

Late last month, the networking equipment maker had to scramble when its acting chief financial officer, Tom Minichiello, announced plans to retire on July 12 to become the new CFO at Westell Technologies (NASDAQ:WSTL). On Friday, though, just as the deadline was happening, Tellabs announced that it has found a replacement.

Tellabs is bringing in audit firm Crowe Horwath partner Larry Rieger to take Minichiello's old job. Strangely, though, despite praising Rieger's "deep expertise in finance, plus more than a decade of experience working with our finance team," Tellabs named him only "acting" CFO, suggesting this appointment, too, may be only temporary.

In related news, the company announced that it has promoted finance director Michael Miles to the position of chief accounting officer -- and this appointment, at least, appears to be permanent.

Fool contributor Rich Smith and The Motley Fool have no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.