You can make it similar with Sparkle (and perhaps more of a logical process to your client in the general scheme):
- Create a normal form submission
- Ask to your client an email address where he would like to read these signings and messages
- Have a selection list of those who’ll join the wall
- Update it weekly or monthly on the page
The thing is, these “direct” text input situations in a website (which i believe is what your client is asking for) aren’t really safe. Also, for this kind of situation where information is exchanged, you would need a database (get the info, hold the info, display the info), which Sparkle does not do by itself.
The “human” curation of the signings can make great opportunities to exchange dialogue and conversations between your client and their costumers, so thats really a plus benefit for your client.
Hope I could give you some light and hope you solve this out with your client