XMLTable Problem - works in PL/SQL, why not standalone?

Question

What is going on here? Why does the plain SQL return this really helpful error?
<pre>
SQL> desc CRMAUTOSAVE
Name Null? Typ
AS_AUTOSAVEID NOT NULL NUMBER(10)
AS_IDENT NOT NULL VARCHAR2(250)
AS_DATA XMLTYPE
CREATEDATE NOT NULL TIMESTAMP(6)
CREATOR NOT NULL VARCHAR2(35)
DELETEFLAG NOT NULL NUMBER(1)
DELETEDATE TIMESTAMP(6)
DELETEBY VARCHAR2(35)
MODIFICATEDATE TIMESTAMP(6)
MODIFICATOR VARCHAR2(35)
SQL> select count(*) from CRMAUTOSAVE;
COUNT(*)
14
SQL> select t2.*
2 from CRMAUTOSAVE
3 , XMLTable('//Attachment'
4 passing CRMAUTOSAVE.AS_DATA
5 columns
6 ATTID number(10) PATH '/Attachment/@Id'
7 ) t2;
ATTID number(10) PATH '/Attachment/@Id'
FEHLER in Zeile 6:
ORA-01780: string literal required
SQL> set serverout on size 100000
SQL> declare
2 cursor c is
3 select t2.*
4 from CRMAUTOSAVE
5 , XMLTable('//Attachment'
6 passing CRMAUTOSAVE.AS_DATA
7 columns
8 ATTID number(10) PATH '/Attachment/@Id'
9 ) t2;
10
11 begin
12 for x in c loop
13 dbms_output.put_line(x.ATTID);
14 end loop;
15 end;
16 /
4455225736
4449873735
PL/SQL-Prozedur erfolgreich abgeschlossen.
</pre>

Answer 1

Further Info:
<pre>
SQL*Plus: Release 10.2.0.1.0 - Production on Mo Feb 15 15:29:08 2010
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Kennwort eingeben:
Verbunden mit:
Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - 64bit Production
With the Partitioning, OLAP and Data Mining options
</pre>
This is a 10.2.0.3 on SunOS 5.10, Sparc. We connect (apparently) with a 10.2.0.1 windows client.
It now gets even better, this one works!
<pre>
SQL*Plus: Release 10.2.0.4.0 - Production on Mon Feb 15 17:30:52 2010
Copyright (c) 1982, 2007, Oracle. All Rights Reserved.
Enter password:
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, Oracle Label Security, OLAP, Data Mining Scoring Engine
and Real Application Testing options
SQL>
SQL>
SQL>
SQL>
SQL> select t2.*
2 from CRMAUTOSAVE
3 , XMLTable('//Attachment'
4 passing CRMAUTOSAVE.AS_DATA
5 columns
6 ATTID number(10) PATH '/Attachment/@Id'
7 ) t2;
ATTID
4385310450
4435025574
</pre>
This is a 64-bit 10.2.0.4, running on Debian Lenny. Client is a 10.2.0.4 windows.
I will experiment a bit with different combinations ;)