(1) Any person who becomes an employee on or after the date of establishment of the retirement system shall become a member of the retirement system upon employment. Contributions by such employee under the Class V School Employees Retirement Act shall begin with the first payroll period after becoming a member, and creditable service shall then begin to accrue.

(2) Any employee who qualifies for membership in the retirement system pursuant to subsection (1) of this section may not be disqualified for membership in the retirement system solely because such employee also maintains separate employment which qualifies the employee for membership in another public retirement system, nor may membership in this retirement system disqualify such an employee from membership in another public retirement system solely by reason of separate employment which qualifies such employee for membership in this retirement system.