Erro qdo instalo um tema Warning: session_start() [function.session-st

Olá Pessoal

A empresa onde trabalho comprou um tamplate para wordpress mas não consigui fazer funcionar no servidor.

Rodando na minha máquina local funciona sem problemas, mas qdo instalo no servidor dá o seguinte erro:

Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at D:\Web\site_connexion\wp-content\themes\theme1119\functions.php:702) in D:\Web\site_connexion\wp-content\plugins\si-contact-form\si-contact-form.php on line 940

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at D:\Web\site_connexion\wp-content\themes\theme1119\functions.php:702) in D:\Web\site_connexion\wp-content\plugins\si-contact-form\si-contact-form.php on line 940

e quando tento acessar o wp-admin aparece os seguintes erros:

Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at D:\Web\site_connexion\wp-content\themes\theme1119\functions.php:702) in D:\Web\site_connexion\wp-content\plugins\si-contact-form\si-contact-form.php on line 940

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at D:\Web\site_connexion\wp-content\themes\theme1119\functions.php:702) in D:\Web\site_connexion\wp-content\plugins\si-contact-form\si-contact-form.php on line 940

Warning: Cannot modify header information - headers already sent by (output started at D:\Web\site_connexion\wp-content\themes\theme1119\functions.php:702) in D:\Web\site_connexion\wp-includes\pluggable.php on line 886

Se alguém poder me ajudar o endereço temporario do site é esse:

http://extranet.connexion.com.br/siteconnexion

Não sei o que acontece lá no servidor pois em minha máquina (win xp) consegui fazer funcionar normalmente, me ajudem por favor..