If the differences among machines/environments consistently fall into just those two possibilities (dd.mm.yyyy versus mm/dd/yyyy), then the following should do what you want: 
s{
   (\d{1,2}) ([./])
   (\d{1,2}) \2
   (\d{4}) \s+ (\d{1,2}):(\d{2})
 }
 {
   my @a=($2 eq ".") ? ($4,$3,$1) : ($4,$1,$3);
   sprintf( "%s-%02d-%02d %02d:%s", @a,$5,$6 )
 }ex;

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The re-ordering of the first three fields depends on whether the field separators are periods or slashes, and the sprintf for the output format makes sure to include leading zeroes when necessary.

(updated to try improving legibility of the code -- not sure I succeeded)

In reply to Re: Question on date formatting by graff
in thread Question on date formatting by KarthikK

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