I have this too.
alias test {
window -bdehik0 -t3,6,14,27,43,51,55 @bla -1 -1 720 300 | font @bla 10 Tahoma
var %t = $chr(9) | aline @bla A %t B %t C %t D %t E %t F %t G %t H
}
In 6.17 the letters are much closer to eachother than in 6.16.
I tried several fonts and it appears the difference between 6.16 and 6.17 happens only for TrueType fonts.