Good point !
With the backslash, it works:
<pre>
# if [ "5.7.1" \> "5.7.22" ]; then echo bigger; else echo smaller; fi
smaller
</pre>
<pre>
# if [ "5.7.10" \> "5.7.22" ]; then echo bigger; else echo smaller; fi
smaller
</pre>
<pre>
# if [ "5.7.10.1" \> "5.7.22" ]; then echo bigger; else echo smaller; fi
smaller
</pre>