As far as I know, it's just a convenience, like words with the prefix in- followed by a p. Since n and p are hard to pronounce in a row, the n is replaced by an m, and all of a sudden we have a new prefix im-.

Which words may start with "al-"?
{msg desc="Says hello and tells user to click a link."}
  Hello {$userName}! Please click &lt;a href="{$url}"&gt;here&lt;/a&gt;.
{/msg}


what set config file or request params in plovr?
