We are planning to use service desk as a complaints system , Where we are creating any complaint from our customer as a ticket. 

Every thing is going smoothly, the last point is: We need to send  SMS to the requester when the request is added. 

We have SMS portal that we can send SMS by sending email with particular subject to "mobile number"@xxxx.xxx

by using the field E-Mail ID to notify we are able to send SMS to the requester. 

now the problem is that  we are not able to change the field  ( E-mail ID to notify ) name and we can not set @xxxx.xxx to be a default value. 

Any suggestions ? to how we can set a default value in the field (E-mail ID to notify ) and change its name ? 

Thanks.