A method for processing contents of a SIP message, comprising: receiving (S12; S21; S32; S36; S45; S56; S66; S76; S82; S94), by a SIP network content processing entity, a SIP message: setting, by the SIP network content processing entity, message contents of the SIP message in accordance with a message content management policy characterized by the fact that the setting the message contents of the SIP message comprises: determining, by the SIP network content processing entity, whether the message content management policy allows to add, modify and/or delete a media component in the SIP message;and adding, modifying and/or deleting (S22, S23; S37; S46; S57; S67; S77; S83) the media component in the SIP message if the message content management policy allows to add, modify and/or delete the media component in the SIP message in accordance with media content information carried in the SIP message, wherein the media component comprises a media content or a reference to a media content, or, the media content and the reference to the media content. receiving (S12; S21; S32; S36; S45; S56; S66; S76; S82; S94), by a SIP network content processing entity, a SIP message: setting, by the SIP network content processing entity, message contents of the SIP message in accordance with a message content management policy characterized by the fact that the setting the message contents of the SIP message comprises: determining, by the SIP network content processing entity, whether the message content management policy allows to add, modify and/or delete a media component in the SIP message;and adding, modifying and/or deleting (S22, S23; S37; S46; S57; S67; S77; S83) the media component in the SIP message if the message content management policy allows to add, modify and/or delete the media component in the SIP message in accordance with media content information carried in the SIP message, wherein the media component comprises a media content or a reference to a media content, or, the media content and the reference to the media content. setting, by the SIP network content processing entity, message contents of the SIP message in accordance with a message content management policy characterized by the fact that the setting the message contents of the SIP message comprises: determining, by the SIP network content processing entity, whether the message content management policy allows to add, modify and/or delete a media component in the SIP message;and adding, modifying and/or deleting (S22, S23; S37; S46; S57; S67; S77; S83) the media component in the SIP message if the message content management policy allows to add, modify and/or delete the media component in the SIP message in accordance with media content information carried in the SIP message, wherein the media component comprises a media content or a reference to a media content, or, the media content and the reference to the media content. determining, by the SIP network content processing entity, whether the message content management policy allows to add, modify and/or delete a media component in the SIP message;and adding, modifying and/or deleting (S22, S23; S37; S46; S57; S67; S77; S83) the media component in the SIP message if the message content management policy allows to add, modify and/or delete the media component in the SIP message in accordance with media content information carried in the SIP message, wherein the media component comprises a media content or a reference to a media content, or, the media content and the reference to the media content.