Apache 2.2.4: Strange HTTP dummy requests on SSL port

Hi,

I got this kind of log entries in my apache logs in Apache 2.2.4:
localhost [127.0.0.1] - - [20/Sep/2007:16:35:54 +0200] "GET /" 400 534
"-" "-" 0 ssl.myhost.tld
localhost [127.0.0.1] - - [20/Sep/2007:16:35:55 +0200] "GET /" 400 534
"-" "-" 0 ssl.myhost.tld
localhost [127.0.0.1] - - [20/Sep/2007:16:35:56 +0200] "GET /" 400 534
"-" "-" 0 ssl.myhost.tld
localhost [127.0.0.1] - - [20/Sep/2007:16:35:57 +0200] "GET /" 400 534
"-" "-" 0 ssl.myhost.tld
localhost [127.0.0.1] - - [20/Sep/2007:16:35:58 +0200] "GET /" 400 534
"-" "-" 0 ssl.myhost.tld
localhost [127.0.0.1] - - [20/Sep/2007:16:35:59 +0200] "GET /" 400 534
"-" "-" 0 ssl.myhost.tld

I tried to sniff the connection but I got only this in one packet:
User-Agent: Ap

then it was cut off. The dummy requests repeats all the time and apache
responds with error 400 bad request, because this request are done on
the SSL port 443.
Does somebody knows what this is?

--
Regards,
Trinity Of Matrix
E-Mail (only for spammer): trinity.matrix@localhost.localdomain