Can I connect (parallel) cell phone batteries?

From: Q (oink_at_gazeta.gov.pl)
Date: 09/04/04 

Date: Sat, 4 Sep 2004 13:10:44 +0200

Hi,

I want to increase siemens c35 (cell phone)
working time;

Can I connect (parallel) 2 or more
cell phone batteries?

Choose Li-Ion, polymer or another?

/the batteries will be the same type, model, capacity, ...

Best regards,
                                    Q