I confirm this bug, with the latest avast! build:
1104 9.53.00,3163750 ashServ.exe 1056 CreateFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Access: Generic Read, Disposition: Open, Options: Synchronous IO Non-Alert, Non-Directory File, Attributes: n/a, ShareMode: Read, Write, Delete, AllocationSize: n/a
1105 9.53.00,3167585 ashServ.exe 1056 QueryNameInformationFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Name: \programs\Alwil Software\Avast4\DATA\avast4.ini
1106 9.53.00,3172497 ashServ.exe 1056 LockFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Exclusive: False, Offset: 0, Length: 7.327.059.152
1107 9.53.00,3180520 ashServ.exe 1056 QueryStandardInformationFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS AllocationSize: 12.288, EndOfFile: 9.570, NumberOfLinks: 1, DeletePending: False, Directory: False
1108 9.53.00,3185576 ashServ.exe 1056 ReadFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Offset: 0, Length: 9.570
1110 9.53.00,3191533 ashServ.exe 1056 UnlockFileSingle C:\programs\Alwil Software\Avast4\DATA\avast4.ini RANGE NOT LOCKED Offset: 0, Length: 6.239.324.605.684
1111 9.53.00,3194854 ashServ.exe 1056 CloseFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS
1112 9.53.00,3200045 ashServ.exe 1056 CreateFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Access: Generic Read, Disposition: Open, Options: Synchronous IO Non-Alert, Non-Directory File, Attributes: n/a, ShareMode: Read, Write, Delete, AllocationSize: n/a
1113 9.53.00,3203981 ashServ.exe 1056 QueryNameInformationFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Name: \programs\Alwil Software\Avast4\DATA\avast4.ini
1114 9.53.00,3208945 ashServ.exe 1056 LockFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Exclusive: False, Offset: 0, Length: 7.327.059.152
1115 9.53.00,3212490 ashServ.exe 1056 QueryStandardInformationFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS AllocationSize: 12.288, EndOfFile: 9.570, NumberOfLinks: 1, DeletePending: False, Directory: False
1116 9.53.00,3216430 ashServ.exe 1056 ReadFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Offset: 0, Length: 9.570
1117 9.53.00,3222819 ashServ.exe 1056 UnlockFileSingle C:\programs\Alwil Software\Avast4\DATA\avast4.ini RANGE NOT LOCKED Offset: 0, Length: 6.239.324.605.684
1118 9.53.00,3226107 ashServ.exe 1056 CloseFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS
1120 9.53.00,3231496 ashServ.exe 1056 CreateFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Access: Generic Read, Disposition: Open, Options: Synchronous IO Non-Alert, Non-Directory File, Attributes: n/a, ShareMode: Read, Write, Delete, AllocationSize: n/a
1121 9.53.00,3238178 ashServ.exe 1056 QueryNameInformationFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Name: \programs\Alwil Software\Avast4\DATA\avast4.ini
1122 9.53.00,3243198 ashServ.exe 1056 LockFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Exclusive: False, Offset: 0, Length: 7.327.059.152
1123 9.53.00,3246749 ashServ.exe 1056 QueryStandardInformationFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS AllocationSize: 12.288, EndOfFile: 9.570, NumberOfLinks: 1, DeletePending: False, Directory: False
1124 9.53.00,3250722 ashServ.exe 1056 ReadFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS Offset: 0, Length: 9.570
1125 9.53.00,3260902 ashServ.exe 1056 UnlockFileSingle C:\programs\Alwil Software\Avast4\DATA\avast4.ini RANGE NOT LOCKED Offset: 0, Length: 6.239.324.605.684
1126 9.53.00,3265858 ashServ.exe 1056 CloseFile C:\programs\Alwil Software\Avast4\DATA\avast4.ini SUCCESS