Weird conn test ping output

Today I have a conn test that is saying this:
x.x.105.219 is alive (54.7 ms) [<- x.x.98.226]

The history has always said this:
x.x.105.XXX

What's with the square bracket IP???

Josh Luthman
Office: XXX-XXX-XXXX
Direct: XXX-XXX-XXXX
XXXX Wayne St
Suite XXXX
Troy, OH XXXXX

Those who don't understand UNIX are condemned to reinvent it, poorly.
--- Henry Spencer