Section 15. (1) Except as provided in paragraph (2), all partners are liable:

(a) Jointly and severally for everything chargeable to the partnership under sections thirteen and fourteen.

(b) Jointly for all other debts and obligations of the partnership; but any partner may enter into a separate obligation to perform a partnership contract.

(2) Subject to the provisions of paragraph (3), a partner in a registered limited liability partnership shall not be personally liable directly or indirectly, including, without limitation, by way of indemnification, contribution, assessment or otherwise, for debts, obligations and liabilities of or chargeable to such partnership, whether in tort, contract or otherwise arising while the partnership is a registered limited liability partnership.

(3) Paragraph (2) shall not affect (a) the liability of a partner in a registered limited liability partnership arising in whole or in part from such partner's own negligence, wrongful acts, errors or omissions, (b) the availability of partnership property to satisfy debts, obligations and liabilities of the partnership or (c) the persons on whom process may be served in an action against the partnership.

(4) Notwithstanding paragraphs (2) and (3), the personal liability of a partner in a limited liability partnership engaged in the rendering of professional services shall not be less than the personal liability of a shareholder of a professional corporation organized under chapter one hundred and fifty-six A engaged in the rendering of the same professional services.