Payment notifications???

Hi, I just started using ZOHO billing and invoicing for my web design and web hosting business, I was using intuit quickbooks but the deal is better here for the price and amount of things I can do for 14 dollars less each month is great. I have successfully set it all up and moved all of my clients and customers into it and began to send invoices which have been paid thru paypal. But I am not getting a payment made response from zoho invoice and so far i have had to go in and manually tell zoho that the bill was paid. This is very inconvenient for me in the respect that I all ready have tons to do everyday and I don't have time to go in and manually tell zoho that every payment was made and manually manage everything so that I can see the book keeping aspect of the system, lol. So, how can I make zoho tell me when one of the invoices was paid thru PayPal and how can I get it to handle that info in the system properly? Is there a code i can drop into the PayPal link in clients emails that will report back to my zoho account or and API key or IPN token that can report the payment status to zoho thus adjusting my books automatically for me? I mean in the manner of adjusting the totals for each client when they make the payment so that when I log in all I have to do is quickly look at the home page and see whos paid and whos behind and all? Im wondering if i missed a check box somewhere or a setting on the set-up or is this not something that zoho can do? I pruchased the zoho service to automate alot of my business ( meaning taking monthly payments for hosting services and web site maintenance and invoices for web design services and all with out much intervention from me) "Seperate note*" **( i do know that I have to manually build clients and customers invoices and I have to set up items and I can set up products and reoccurring billing and all, but those are like set it and forget it settings largely, I am mostly worried about making the invoices get sent at the same time every month and being able to quickly look to see who has paid them and who has not with out me having to login to pay pay or check my emails and look for paypal emails, lol. Anyways, any input would be greatly appreciated. Thanks - Ps I did search these forums for this problem but found nothing, so if this is a duplicate post or problem i am sorry...