1. A method for providing redirection functionality in a telecommunications network having a Charging Trigger Function (CTF) and an online charging system (OCS), the method comprising: providing a Session Redirection Module in a Service Capability Interaction Manager (SCIM) in the telecommunications network; initiating by the CTF a credit communication session from the CTF to the OCS through the SCIM; receiving at the SCIM from the CTF a first Credit Control Request (CCR) message, the first CCR message including a first credit communication session identifier used by the CTF to identify the credit communication session; forwarding the first CCR message by the SCIM to the OCS as a second CCR message, the second CCR message including a second credit communication session identifier used by the SCIM to identify a first portion of the credit communication session initiated by the CTF between the SCIM and the OCS; receiving at the SCIM from the OCS via the credit communication session a first Credit Control Answer (CCA) message directed to the CTF, the first CCA message being responsive to the second CCR message and including the second credit communication session identifier; comparing the first CCA message against criteria for redirection using the Session Redirection Module and determining as a first result of the comparing that the first CCA message does not meet the criteria for redirection; responsive to determining as the first result of the comparing that the first CCA message does not meet the criteria for redirection, forwarding the first CCA message which does not meet the criteria for redirection from the SCIM to said CTF via the credit communication session as a first response CCA message, the first response CCA message including the first credit communication session identifier used by the CTF to identify the credit communication session; subsequent to receiving the first CCR message at the SCIM and forwarding the first response CCA message from the SCIM to the CTF, receiving at the SCIM from the CTF a third CCR message, the third CCR message including the first credit communication session identifier used by the CTF to identify the credit communication session; forwarding the third CCR message by the SCIM to the OCS as a fourth CCR message, the fourth CCR message including a third credit communication session identifier used by the SCIM to identify a second portion of the credit communication session initiated by the CTF between the SCIM and the OCS; receiving at the SCIM from the OCS via the credit communication session a second CCA message directed to the CTF, the second CCA message being responsive to the fourth CCR message and including the third credit communication session identifier; comparing the second CCA message against the criteria for redirection using the Session Redirection Module and determining as a second result of the comparing that the second CCA message does meet the criteria for redirection; and responsive to determining as the second result of the comparing that the second CCA message does meet the criteria for redirection: terminating by the SCIM the second portion of the credit communication session between the SCIM and the OCS; augmenting by the SCIM the second CCA message which does meet the criteria for redirection as a Redirection CCA message by inserting redirection information associated with an associated service delivery credit unit top-up application into the second CCA message which does meet the criteria for redirection, thereby forming the Redirection CCA message, wherein the Redirection CCA message includes the first credit communication session identifier used by the CTF to identify the credit communication session; transmitting in the credit communication session the Redirection CCA message from the SCIM to the CTF, wherein the inserted redirection information of the Redirection CCA message redirects the credit communication session by the CTF towards the associated service delivery credit unit top-up application without terminating the credit communication session between the CTF and the SCIM; receiving in the credit communication session at the SCIM from the CTF a fifth CCR message providing updated credit control information to the OCS, the fifth CCR message having the first credit communication session identifier used by the CTF to identify the credit communication session; initiating by the SCIM a new portion of the credit communication session between the SCIM and the OCS responsive to receiving the fifth CCR message including the first credit communication session identifier used by the CTF to identify the credit communication session; and forwarding a sixth CCR message in the new portion of the credit communication session by the SCIM to the OCS, the sixth CCR message comprising the fifth CCR message and having a fourth credit communication session identifier used by the SCIM to identify the new credit communication session initiated by the SCIM between the SCIM and the OCS.