Problems with user passwords

Question

Hello All, I'm learning how to use databases at the moment and came across something that caused many headaches for me. It was enough for me to post this to see what others out there thought about the issue, if it is even an issue at all.
Ill try to be concise but as short as possible.
Background:
Installed Oracle 10g XE
Created a new user using the database homepage
New user details:
User: dan
Pass: (the password was fairly 'random' it happen to start with @)
When i opened CMD within vista OS and typed sqlplus the application opened successfully.
The username and password were entered and i recieved the text below as the response.
Enter user-name: dan
Enter password: @*******
SP2-0306: Invalid Option
Usage: blah blah
It turns out that it was my password that was holding me back, i created a new user with u/p dan/dan and it worked fine. The @ symbol is all i could put it down to, but no where at any point during the creation of the user did it complain about the use of @. But perhaps i was using the system wrong? Enter user name, enter password, seems simple enough.
If this is not a bug of sorts then the error message was very confusing and misleading because i believed i had set it up correctly.
This can be reproduced.
I know there is some really smart dba's out there, what are your thoughts?
Thanks

Answer 1

No belief necessary. Passwords follow object naming rules.
Nonquoted identifiers must begin with an alphabetic character from your database character set. Quoted identifiers can begin with any character.
Nonquoted identifiers can contain only alphanumeric characters from your database character set and the underscore (_), dollar sign ($), and pound sign (#). Database links can also contain periods (.) and "at" signs (@). Oracle strongly discourages you from using $ and # in nonquoted identifiers.
Quoted identifiers can contain any characters and punctuations marks as well as spaces. However, neither quoted nor nonquoted identifiers can contain double quotation marks or the null character (\0).
http://download.oracle.com/docs/cd/B19306_01/server.102/b14200/sql_elements008.htm#sthref723