Dear,
The simplest way is to Hold the petty expense vouchers untill petty cash is received.
If an expense of Rs. 5,000 is borne by the manager and petty cash has a balance of Rs. 500 only, then hold the voucher of Rs. 5,000 untill petty cash cheque / amount is received. As soon as petty cash is received, pay the amount contributed by the Manager and adjust Rs. 5,000 in petty cash / cash book.
The only consequence would be the contradiction in between the dates of incurrence of expenditure and reporting of the same.
Best Regards,
Desperado.