Non-native English?

[Gordon, Matthew J.]

Jim Landau said:

"Do NOT open the file.  "IE" stands for "Internet Explorer", and NOBODY would
send out patches for IE unsolicitated.  "

I was intrigued by "unsolicitated" where I would have 'unsolicited'. A quick google search suggests 'unsolicitate' is fairly common especially in this context of spamming.
Is this another specialized usage for a backformation like commentate (cf. comment)?