[dev] 9base mk doesn't work with subscripts?

[Marc Chantreux]

hello suckless people,

i try to remove my current tools by simpler ones
when it's confortable enough.

here is my make for a simple website:

MKSHELL = rc
sources = `{ echo *.md }
pages   = ${sources:%.md=pub/%.html}
$pages:
pub/%.html: %.md template
    mkpage $prereq(1) > $target

but when building index.html from index.md, i got

    mkpage index.md template(1) > $target

instead of

    mkpage index.md template(1) > $target

before i jump in the mk sourcecode and try to
figure out why it doesn't work, i would like to
get your opinion:

* did i miss something?
* is this a known bug?

regards
marc