Indenting perl data structures

[Peter Westlake]

I have some nested perl data structures that look like this:

[
  "string",
  [
    "more",
    [
      "other",
      "string"
    ],
  ]
]

but the Perl mode indents them like this:

[
 "string",
 [
  "more",
  [
   "other",
   "string"
   ]
  ]
 ]


- where the wrong closing bracket lines up with
the opening bracket. Emacs is using a single character
for indentation, and indenting the close bracket with
respect to the open instead of lining them up. I need
them to line up because the data structures are quite
deeply nested and I'll never get them right otherwise.

There's nothing in the custom buffer for Perl mode
about this, and I can't see anything in perl-mode.el
that mentions square brackets. Any ideas?

Peter.