While relying strictly on md5sums (they change people!) to tell if a server is, or is not compromised is a bad idea, I'll say that fakeguage is not part of the standard CentOS distribution from what I've seen.
That , coupled with the incorrect md5 some hints that you might just have an issue on your server. I wouldn't panic QUITE yet, but you need to get a professional in there looking at things.
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Upload the file to www.virustotal.com and see if it returns any hits for virus/malware files. No guarantee it is not or is, but worth a shot, especially if the virus scanners report a high rate of success.