A few technical podcasters I listen to keep using the term problematical. I didn’t think it was a word, but according to WordNet:

Overview of adj problematical

The adj problematical has 2 senses (no senses from tagged texts)

  1. debatable, problematic, problematical – (open to doubt or debate; “If you ever get married, which seems to be extremely problematic”)

  2. baffling, elusive, knotty, problematic, problematical, tough – (making great mental demands; hard to comprehend or solve or believe; “a baffling problem”; “I faced the knotty problem of what to have for breakfast”; “a problematic situation at home”)

I’ll stick to problematic, but there you go.

Also, you owe it to yourself to install textproc/wordnet, or WordNet from homebrew. Then you can get a definition overview with:

$ wn problematical -over

Or the “-sensa” option, which returned the following synonyms:

Sense 1
debatable, problematic, problematical
=> questionable (vs. unquestionable)

Sense 2
baffling, elusive, knotty, problematic, problematical, tough
=> difficult (vs. easy), hard