[web2py] db.define_tabl('mytable', Field('call-limit')) error when use simbol "-" minus in Field name

[Emilius Omeen]

Hello
thanks Massimo for web2py

models/db.py
db.define_table('cdr', Field('call-limit', 'integer', notnull=True, 
default='3'))

Error 
<type 'exceptions.SyntaxError'> invalid table or field name: call-limit
raise SyntaxError, 'invalid table or field name: %s' % text
SyntaxError: invalid table or field name: call-limit

9.
10.
11.

Traceback (most recent call last):
  File "/home/www-data/web2py/gluon/restricted.py", line 212, in restricted
    exec ccode in environment
  File "/home/www-data/web2py/applications/sip_users/models/db.py" 
<https://10.100.100.104/admin/default/edit/sip_users/models/db.py>, line 45, in 
<module>
    Field('call-limit', 'integer', notnull=True, default='3'),#deprecated
  File "/home/www-data/web2py/gluon/dal.py", line 8431, in __init__
    self.name = fieldname = cleanup(fieldname)
  File "/home/www-data/web2py/gluon/dal.py", line 4831, in cleanup
    raise SyntaxError, 'invalid table or field name: %s' % text
SyntaxError: invalid table or field name: call-limit



I see that if use in Field name any string with included simbol "-" minus. 
May be I do something wrong ?
Or web2py have another way to avoid this error ?

Thak you.

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