ftp problems

[tgansert]

Since the install, I am receiving the following errors in /var/log/proftp:

May 12 07:00:01 host.domain.com proftpd[29458] host.domain.com (127.0.0.1[127.0.0.1]): FTP session closed.
May 12 07:30:02 host.domain.com proftpd[29961] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
May 12 07:30:02 host.domain.com proftpd[29961] host.domain.com (127.0.0.1[127.0.0.1]): FTP session closed.
May 12 07:48:15 host.domain.com proftpd[30353] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
*** glibc detected *** free(): invalid next size (fast): 0x081115d8 ***
May 12 07:49:53 host.domain.com proftpd[30861] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
May 12 07:49:53 host.domain.com proftpd[30861] host.domain.com (127.0.0.1[127.0.0.1]): no such user 'impulse'
May 12 07:49:53 host.domain.com proftpd[30861] host.domain.com (127.0.0.1[127.0.0.1]): USER impulse: no such user found from 127.0.0.1 [127.0.0.1] to 127.0.0.1:21
May 12 07:49:53 host.domain.com proftpd[30861] host.domain.com (127.0.0.1[127.0.0.1]): Maximum login attempts (1) exceeded
May 12 07:49:53 host.domain.com proftpd[30861] host.domain.com (127.0.0.1[127.0.0.1]): FTP session closed.
May 12 07:49:54 host.domain.com proftpd[30869] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
May 12 07:49:54 host.domain.com proftpd[30869] host.domain.com (127.0.0.1[127.0.0.1]): no such user 'impulse'
May 12 07:49:54 host.domain.com proftpd[30869] host.domain.com (127.0.0.1[127.0.0.1]): USER impulse: no such user found from 127.0.0.1 [127.0.0.1] to 127.0.0.1:21
May 12 07:49:54 host.domain.com proftpd[30869] host.domain.com (127.0.0.1[127.0.0.1]): Maximum login attempts (1) exceeded
May 12 07:49:54 host.domain.com proftpd[30869] host.domain.com (127.0.0.1[127.0.0.1]): FTP session closed.
May 12 07:50:07 host.domain.com proftpd[30901] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
*** glibc detected *** corrupted double-linked list: 0x081115f8 ***
May 12 07:50:07 host.domain.com proftpd[30906] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
May 12 07:50:07 host.domain.com proftpd[30906] host.domain.com (127.0.0.1[127.0.0.1]): USER ssneed (Login failed): Invalid shell: '/dev/null'
May 12 07:50:07 host.domain.com proftpd[30906] host.domain.com (127.0.0.1[127.0.0.1]): Maximum login attempts (1) exceeded
May 12 07:50:07 host.domain.com proftpd[30906] host.domain.com (127.0.0.1[127.0.0.1]): FTP session closed.
May 12 07:56:38 host.domain.com proftpd[31120] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
May 12 07:56:38 host.domain.com proftpd[31120] host.domain.com (127.0.0.1[127.0.0.1]): USER ssneed: Login successful.
May 12 11:56:38 host.domain.com proftpd[31120] host.domain.com (127.0.0.1[127.0.0.1]): FTP session closed.
May 12 07:56:38 host.domain.com proftpd[31127] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
*** glibc detected *** corrupted double-linked list: 0x081115e8 ***
May 12 07:56:44 host.domain.com proftpd[31137] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
*** glibc detected *** corrupted double-linked list: 0x081115b0 ***
May 12 08:00:01 host.domain.com proftpd[31228] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
May 12 08:00:01 host.domain.com proftpd[31228] host.domain.com (127.0.0.1[127.0.0.1]): FTP session closed.
May 12 08:07:14 host.domain.com proftpd[31419] host.domain.com: Failed binding to 0.0.0.0, port 21: Address already in use
May 12 08:07:14 host.domain.com proftpd[31419] host.domain.com: Check the ServerType directive to ensure you are configured correctly.
May 12 08:07:30 host.domain.com proftpd[21723] host.domain.com: ProFTPD killed (signal 15)
May 12 08:07:30 host.domain.com proftpd[21723] host.domain.com: ProFTPD 1.2.10 standalone mode SHUTDOWN
May 12 08:07:32 host.domain.com proftpd[31436] host.domain.com: ProFTPD 1.2.10 (stable) (built do mrt 22 18:28:32 CET 2001) standalone mode STARTUP
May 12 08:07:51 host.domain.com proftpd[31436] host.domain.com: ProFTPD killed (signal 15)
May 12 08:07:51 host.domain.com proftpd[31436] host.domain.com: ProFTPD 1.2.10 standalone mode SHUTDOWN
May 12 08:07:54 host.domain.com proftpd[31597] host.domain.com: ProFTPD 1.2.10 (stable) (built do mrt 22 18:28:32 CET 2001) standalone mode STARTUP
May 12 08:08:14 host.domain.com proftpd[31617] host.domain.com (127.0.0.1[127.0.0.1]): FTP session opened.
*** glibc detected *** free(): invalid next size (fast): 0x08111598 ***

Can anyone tell me the cause/repair?