The Commissioner of Mental Health and Substance Abuse Services shall classify as a part of the Merit System of Personnel Administration all positions for which there are established Merit System Classifications, except those positions unique to hospital and clinic functions, those positions held by employees of the Department of Mental Health and Substance Abuse Services who perform behavioral health services, those positions in facilities that were formerly privately operated but are now under the operational and management control of the Department, or those associated administrative and support employees whose salaries are paid from contractual agreements with managed care companies, health maintenance organizations, preferred provider organizations, hospital or health care networks, insurance plans, private business or other government agencies; provided, the employment of personnel whose salaries are paid from such contractual agreements shall be limited to the duration of the contracts or renewals thereof under which such personnel are employed. Provided further, no employee shall have the salary of that employee decreased as a result of the classification action herein directed.