Is there any exploit circulating ?

Greeting Drupals,

My web site runs on Drupal and lately I'm seeing lot of access denied logs. First I thought that these logs came from my users but when examine IP addresses I concluded that these logs are not coming from my users. IP addresses registered on Drupal are from MS Cooperation, China Telecom, Inktomi Corporation etc, and since my website is on my local language It can’t be that users are trying to connect from this part of the world specially China. Furthermore I don’t think someone from M$ or other mentioned cooperation would like to see my users profile. (see logs below)

Firstly it looks to me like some kind of exploit and I’m writing here to see if any of you is aware of any exploit circulating?
Another strange thing is that it seems that IP’s are spoofed. Since HTTP is used does it make any sense to do so?

Site runs on Drupal 4.6.1

Here are some logs registered on my Drupal. I’ve selected only type of log and location requested. ( I didn’t post IP addresses but if someone sees same logs and wants to compare IP addresses I’ll post them ). TOP 20

LOG

access denied /?q=profile/gender/male
access denied /?q=user/616
access denied /profile/
access denied /?q=user/591
access denied /?q=user/7
access denied /?q=user/670
access denied /?q=user/3
access denied /?q=user/5
access denied /?q=user/1807
access denied /?q=user/5
access denied /?q=user/1807
access denied /?q=user/638
access denied /?q=user/7
access denied /?q=user/530
access denied /?q=user/179
access denied /?q=user/2
access denied /?q=user/39
access denied /?q=user/621
access denied /?q=user/2
access denied /?q=user/39

ENDLOG

Best regards,
lamer1