using variables in eregi_replace("

[Anon]

what's the common work-around to echoe variables within an eregi_replace string? i can't seem to be able to?

example is at "target":
$ret = eregi_replace("([[:alnum:]]+)://([^{[:space:]]*)([[:alnum:]#?/&=])",} "<a href=\"\1://\2\3\" target=\"$links_target\">\1://\2\3</a>", $text);

thanks