setting file attribs

can i set my own file attribs like KFileEncrpted rather than using symb att ....can i use Reserved,File System Specific , add space for setting my own att.

As symbian has provided these attribs
0 - KEntryAttReadOnly
1 - KEntryAttHidden
2 - KEntryAttSystem
3 - KEntryAttVolume

4 - KEntryAttDir
6 - KEntryAttArchive
7 - KEntryAttXIP

8 - KEntryAttRemote
9 - Reserved
10 - Reserved
11 - Reserved

12 - Reserved
13 - Reserved
14 - Reserved
15 - Reserved

16 - File System Specific
17 - File System Specific
18 - File System Specific
19 - File System Specific

20 - File System Specific
22 - File System Specific
22 - File System Specific
23 - File System Specific

24 - Reserved
25 - Reserved
26 - Reserved
27 - KEntryAttMatchExclude

28 - KEntryAttAllowUid
29 - Reserved
30 - KEntryAttMatchExclusive
31 - Reserved