There is still one contract outstanding, and with Irish centre Kevin Maggs turning down a move to the province, Ulster may return to New Zealand.
They are at present talking to a player with All Blacks experience, and is a prominent member of the Highlanders Super 12 side.
Mustchin, who is European qualified and a former New Zealand under-19 back-row forward, has also Super 12 experience.
While he has played mostly at loose forward, Ulster could utilise him in the second row following the retirement of Jeremy Davidson and the loss of Mark Blair to Narbonne.
Solomons is obviously pleased with his new acquisition who can fill any position in the back five.
''Matt is a very physical, rugged and robust player, and has the pedigree coming from the Crusaders squad who are leading side in the Super 12 for the past three seasons.
''I do believe he will be a massive asset to us at Ravenhill this season,'' said Solomons who spokdes of the number of young players coming through the ranks.
''It pleases me in that my vision of what would happen in Ulster is coming to fruition. The province will soon become self-generating.
''In the past two years we have been bleeding in the youth, but this season it has been very positive indeed,'' said Solomons who will have some of his youngsters to fill gaps in a busy season of 31 games.
The youthful new faces for next season are Irish under-21 and Queen's full-back Tommy Bowe, Tim Barker, Seamus Mallon, Andy Maxwell and Gary Brown.
Scrum-half Reece Spee, who has moved from City of Derry to Belfast Harlequins, has had his part-time contract upgraded for next season.
Ulster had already signed up Connacht duo Ronan McCormack and Rowan Frost at the tailend of last April.
Ulster will have Academy player Glenn Telford at their disposal during the start of the season.
The Irish under-21 and Dungannon centre was not included in the final squad shake-up for a senior contract due to his ophthalmic studies.
Forwards: T Barker, N Best, S Best, C Boyd, N Brady, W Brosnihan, G Brown, R Frost, R Kempson, G Longwell, R McCormick, m McCullough, N McMillan, T McWhirter, M Mustchin, M Sexton, P Shields, A Ward, R Wilson, B Young.
Backs: J Bell, T Bowe, K Campbell, R Constable, B Cunningham, N Doak, T Howe, D Humphreys, A Larkin, S Mallon, A Maxwell, R Spee, S Stewart, J Topping, P Wallace, S Young.